Dr Scott Turner


Senior Lecturer in Solid State Materials, Director of Learning and Teaching for Chemistry
BSc(Hons) MRSC PhD
+44 (0)1483 686847
33 AZ 03

Academic and research departments

Department of Chemistry.

Biography

Areas of specialism

Coordination chemistry; Molecular Materials; Magnetic properties; Electrical and ionic conductivity; Metal organic frameworks

University roles and responsibilities

  • Director of Learning and Teaching
  • University Academic Integrity Officer

    My qualifications

    1990
    BSc (Hons) in chemistry
    University of Manchester
    1993
    PhD in chemistry: synthesis of coordination polymers and EPR spectroscopy
    University of Manchester

    Affiliations and memberships

    MRSC
    Member of the Royal Society of Chemistry

    Research

    Research interests

    Research collaborations

    My teaching

    Courses I teach on

    Undergraduate

    My publications

    Publications

    SCOTT STEVEN TURNER, (2020)Different electronic states of isomorphous chiral vs. racemic organic conducting salts, β′′-(BEDT-TTF)2(S- and rac-PROXYL-CONHCH2SO3), In: Materials Advances2020(1)pp. 3171-3175 Royal Society of Chemistry
    The chiral and racemic salts β′′-(BEDT-TTF)2(S- and rac-PROXYL-CONHCH2SO3) (S-2 and rac-2) are almost isomorphous apart from a deviation in the C–H bond direction at the chiral centre. Both salts are metallic at room temperature, with similar broad metal-insulator transitions. Band structure calculations of the chiral and racemic salts indicate that both electronic structures are quite similar. However, at 30 K, S-2 has a resistivity that is nearly three orders of magnitude higher than that of rac-2. The results suggest a significant effect of the broken inversion symmetry, due to the positional change of only one atom.
    Hiroki Akutsu, Akiko Kohno, Scott S Turner, Yasuhiro Nakazawa (2020)Structure and Properties of a New Purely Organic Magnetic Conductor, δ´-(BEDT-TTF)2(PO-CONHCH(cyclopropyl)SO3)·1.7H2O, In: Chemistry Letters49(11)pp. 1345-1348
    A purely-organic magnetic charge-transfer salt, δ¤-(BEDT-TTF) 2 (PO-CONHCH(cyclopropyl)SO 3)¢1.7H 2 O, has been prepared. Conducting layers consist of BEDT-TTF tetramers, in which two holes are localized, which obeys a Singlet-Triplet model. The similarity between the semiconductor-to-semiconductor transition temperature and the temperature where triplet excitation becomes negligible, suggesting that the conductions of spin singlet and triplet states become dominant in the lower and higher temperatures, respectively.
    A series of Ru complex ions, [Ru(bpy)2X]+ (bpy = bipyridyl) were synthesized. This was with a view to studying their photophysical properties by experimental and computation methods. In particular the effect of pH, concentration, temperature and the nature of ligand X has been investigated. The X-ligand represents pyridine, pyrazine or pyrimidine derivatives of 1,2 and 1,3 diazolates, 1,2,3 and 1,2,4 triazolates and 1,2,3,4 tetrazoles. Four of the compounds were studied by experimental photophysical and computational methods, namely pyridine and pyrazine derivative of 1,2-diazolate and 1,3-diazolate. The selection of the ligands also demonstrates the effect of the nitrogen content and nitrogen position on the absorption and emission properties of the complexes, as well as on the pH optical response of the [Ru(bpy)2X]+/[Ru(bpy)2XH]2+ in the absorption spectra. The dual state emission behaviour has also been studied in detail to elucidate the unexpected switching of the most prominent low energy emission band. The absorption and emission properties of the deprotonated and protonated complex ions were characterised by UV-vis and photoluminescence spectroscopy, as well as by time-dependent density functional theory. The 1MLCT transition with d-πazo-π*bpy character exhibit a tunability range of ~17 nm from experimental results and estimated to be ~33 nm from calculations. The X ligand shows a relatively small change on the first absorption band. When the six-membered ring of the X ligand has a higher nitrogen content the absorption wavelengths for the (d-πazo)-π*bpy transition shifts to lower wavelengths. A blue shift is also observed when comparing the position of the N atoms at the 1, and 2 or 1 and 3 positions of the azolate on the X ligand. Modification of the nitrogen content and nitrogen position within the protonatable/deprotonatable ligands is an effective approache for modulation of the pH-optosensing properties of Ru-polypyridyl complexes. The dual emission is shown to arise from the presence of two excited states consisting of a triplet metal-to-ligand charge transfer state localized on a bipyridine ligand - 3MLCT (bpy), and either a state that is entirely localized on the X ligand or is partially delocalized also spanning part of the bipyridine ligands - 3MLCT(X). The choice of the X ligand modulated the emission of the 3MLCT(bpy) and 3MLCT(X) states between 743 - 865 nm and from 555 - 679 nm, respectively. A blue shift of the 3MLCT(bpy) emission on increasing the nitrogen content of the six-membered ring of the X ligand is observed while by contrast a redshift for the 3MLCT(X) emission. The energy difference between 3MLCT(bpy) and 3MLCT(X) emissions can be tuned from 84–310 nm.
    This work considers interactions occurring between humic acid (HA) and other representative components of oil sands such as sand and clays, and their potential effect on bitumen recovery. Further, it considers the characterisation of oil sand components in terms of physico-chemical and dielectric properties. The study focuses on a combination of artificially prepared systems analysed using a variety of techniques, including dielectric spectroscopy (DS), UV-Vis spectrophotometry (UV-Vis), sedimentation analysis and adsorption isotherms. Finally, it talks about HA extraction from natural oil sands, HA behaviour in solution and its interactions with oil sand components. Dielectric properties arise from electronic and atomic polarisation or dipole, ionic or dielectric relaxation mechanisms. The particular sensitivity of basic electrical measurements, e.g. resistivity, to the presence of water made the original use of this approach most relevant to the determination of water-filled porosity in model oil sand samples. The present study builds on recent developments in the literature, and, specifically determines the extent to which the potentially dominant effects of water can be overcome in order to access additional information, such as wettability. DS was used to study physico-chemical and structural characteristics of artificially prepared simplified oil sand systems. At the low-frequency DS analysis (10-3 – 107 Hz) yields complex properties, which revealed contributions from underlying processes in materials, including electronic, ionic and interfacial polarisation. Dielectric measurements undertaken on a range of artificially prepared samples revealed strong, regular dependencies on the composition of the systems. This model study proved DS to be a valid method for the analysis of complex systems such as synthetically prepared oil sands. The results indicated wettability change in a systematic manner in samples made up of varying combinations of sand, clays, water and bitumen. It has been considered that water-soluble organic species can influence the recovery of bitumen by having an effect on parameters such as wettability or surface charge, thereby altering interactions between oil sand components. HA is of considerable environmental significance, being a major component of soil. However, its structure and colloidal properties continue to be the subject of debate, largely owing to its molecular complexity and association with other humic substances and mineral matter. Natural oil sand (NOS) samples obtained from Alberta, Canada were separated into solid, oil and water fractions. HA was further extracted out of water fractions using a range of procedures. The obtained organic species were identified mainly using Fourier Transform infrared (FTIR) spectroscopy and compared against standard components. The presence of aromatics, alcohols, phenols, ketones and aliphatic and aromatic amines was confirmed in the extracted HA samples. An adsorption study of HA on mineral surfaces was done by means of conductivity measurements. The adsorption of various concentrations of NaHA from the aqueous solutions onto the surface of sand, clay and sand-clay mixtures with varying ratios was studied by means of DS and the UV-vis absorption measurements. The results showed a strong affinity of the HA present in the solutions to the surface of sand and clay. The calculations based on the results obtained proved the significance of clay in the HA-solids interactions. Although the sand surface covered in HA remains naturally hydrophilic (slightly less than a natural sand), it hinders the adsorption of asphaltenes onto the surface. The HA adsorbs onto the asphaltenes coated sand, making the surface increasingly more hydrophobic over time. Colloid and interfacial properties were studied by means of conductivity, surface tension and zeta potential measurements. a class, HA is considered to comprise supramolecular assemblies of heterogeneous species, and herein, a simple route for the separation of some HA sub-fractions was considered. A commercial HA sample has been fractionated into two soluble (S1, S2) and two insoluble (I1, I2) fractions by successive dissolution in deionised water at near-neutral pH. These sub-fractions have been characterised by solution and solid-state methods. Using this approach, the HA has been shown to contain non-covalently bonded species with different polarity and water solubility. The soluble and insoluble fractions have different chemical structures, as revealed particularly by their solid-state properties (13C Nuclear Magnetic Resonance (NMR) and FTIR spectroscopies, and thermogravimetric analysis (TGA)); in particular, S1 and S2 were characterised by higher carbonyl and aromatic content, compared with I1 and I2. The soluble fractions were shown to behave as hydrophilic colloidal aggregates. It was found that HA dissolution is not affected by the temperature change or increase of agitation and it was reduced by the presence of mono- and divalent ions. The negative nature of HA was confirmed and it was found that it flocculates by addition of cationic surfactant. The presence of HA in the solution also showed stabilisation of clay dispersions.
    The following work regards the synthesis and characterisation of compounds with the potential to undergo a spin crossover (SCO). A SCO describes an electronic transition between the LS and HS states in response to perturbation by light, pressure, magnetic-field or thermal stimuli. These materials consist of d4 – d7 first row transition metal ions chelated to a suitable organic ligand system. By inducing a SCO transition, a compound exhibits exploitable changes in magnetism, colour and conductivity, making them candidates for use in information storage media. For conventional systems, the SCO must occur around room temperature with a practical hysteresis. Here, the LS state and HS state can correspond to, for instance, the binary states used in computational memory. Currently, a suitable compound remains elusive. To this end, this thesis challenges the design and development of cationic Fe(II) and Co(II) complexes by intelligent ligand modification. Amide- and thioamide-functionalisation of Fe(II) 2,6-bis(pyrazol-1-yl)pyridine (bpp) complexes, of the form [Fe(ligand)2](X)2, where X = BF4- or ClO4-, has been used to modulate the SCO properties. Complexes were found to exhibit a range of magnetic, from being locked in the LS or HS state, to abrupt SCO with hysteresis up to 96 K. Crystallisation of several compounds was achieved by slow vapour diffusion. Intermolecular hydrogen bonding between NH-groups and anions were responsible for isostructural packing between salts, which led to similar SCO properties. In addition, amide-linked homo- and heterobimetallic coordination polymers were synthesised and found to exhibit gradual SCO, attributed to their amorphous nature. Finally, an attempt was made to establish a more ‘green’ and efficient synthesis of bpp and related ligands. As a result, several novel ligand species and their Fe(II) and Co(II) complexes were synthesised. Amide-functionalised 2,6-bis(benzimidazol-2-yl)pyridine (bbip) Fe(II) complexes were found to exhibit SCO behaviour, while ester functionalised versions persisted in the LS state. Compounds were analysed by TGA, DSC, Evan’s method NMR spectroscopy, SQUID magnetometry, UV/Vis, Raman spectroscopy, single crystal and powder X-ray diffraction. Surface deposits of coordination polymers were also characterised by SEM and AFM following drop casting and spin coating onto silicon wafers. Overall, this has been a highly fruitful investigation leading to a total of 33 novel organic compounds and 46 novel complexes, 26 of which displayed some form of SCO.
    The plasma treatment of few-layer graphene (FLG) was investigated for the effect on the performance in supercapacitors and microsupercapacitors. Modifications to the FLG surfaces were proven by comprehensive studies using characterisation techniques including elemental microanalysis, X-ray photoelectron spectroscopy, potentiometric titration, zeta-potential measurements and dispersion stability analysis. A thermal pre-treatment to yield dried FLG was shown to increase the FLG surface charge and density due to the removal of adsorbed water and incorporation of carboxyl and phenolic functional groups. The thermal treatment was used before all characterisation methods were applied. An Ar gas plasma treatment on dried FLG was shown to introduce carboxyl and phenolic surface functional groups and reduce material variability. With increasing treatment time of Ar plasma, the FLG oxygen content increased by 1 at% due to the presence of a larger number of carboxyl functional groups. The introduction of H2 gas at 3 wt% in Ar gas plasma produced a different functionalised FLG with a smaller quantity of carboxyl groups. Compared to the Ar gas plasma treated material, the H2/Ar gas treated material had a lower surface charge and density. NH3 gas plasma increased the nitrogen content of the FLG starting material two-fold according to XPS and elemental microanalysis. A multi-step treatment consisting of H2/Ar mixed gas plasma followed by NH3 gas plasma gave a further surface increase in nitrogen content by five times relative to the starting material. Electrode films were manufactured using polytetrafluoroethylene (PTFE) and styrene-butadiene rubber (SBR) as non-conductive binders and poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT/PSS) as a conductive binder. The electrode films were constructed into supercapacitors and microsupercapacitors. External testing with PTFE binder showed promise for the H2/Ar mixed gas plasma treated material with a specific capacitance of 195 F g-1 at 1 mA cm-2 in sulfuric acid electrolyte, a 50% increase relative to untreated FLG devices. The other treated materials did not match this performance because they did not contain low concentrations of oxygen surface functional groups and had large quantities of sp3 hybridised carbon atoms. The supercapacitor devices were studied with sulfuric acid and potassium hydroxide aqueous electrolytes. The devices with potassium hydroxide electrolyte did not match the performance of the materials in sulfuric acid electrolyte due to materials’ incompatibilities. Supercapacitor testing was additionally carried out with SBR and carboxymethyl cellulose (CMC) in sandwiched devices alongside potassium hydroxide and sulfuric acid electrolytes. The manufacture of the electrode films required 20 wt% of SBR-CMC binder. The electrochemical results were indistinguishable and had large resistances. An extensive investigation into the manufacture of flexible electrode films with FLG, multi-walled carbon nanotubes (MWCNT) and PEDOT/PSS in composite electrode materials was carried out. The electrode films were laser-etched into interdigitated patterns for planar micro-supercapacitor devices with the application of polyvinylalcohol-phosphoric acid gel electrolyte. These devices performed best with a mass ratio of 1:3:1 (PEDOT/PSS:FLG:MWCNT), and with NH3 functionalised FLG and acid functionalised MWCNT. Gravimetric capacitances of 120 F g-1 at 5 mV s-1 and volumetric capacitances of 20 F cm-3 at 5 mV s-1 were obtained for the NH3:MWCNT(Acid) combination during long cycling tests (10,000 cycles) and showed capacity retentions > 80%. In-situ Raman microscopy analysis suggested that the PEDOT/PSS component underwent pseudo-capacitive, reversible changes during cycling tests but the dominant electric-double layer capacitive-like response was due to the FLG and MWCNT materials, which were highly stable.
    H Akutsu, J-I Yamada, S Nakatsuji, SS Turner (2006)A novel BEDT-TTF-based purely organic magnetic conductor, α - (BEDT - TTF)(TEMPO - N(CH)COCHSO) {dot operator} 3HO, In: Solid State Communications140(5)pp. 256-260
    A new BEDT-TTF-based salt with an organic free radical TEMPO has been prepared. The salt consists of alternate layers of conducting and magnetic sheets, between which are short S(BEDT-TTF) ...O(TEMPO) contacts. The magnetic susceptibility is well modelled by the combination of a 2D Heisenberg and a Curie-Weiss model with J = - 89 K and θ = + 0.05 K. © 2006 Elsevier Ltd. All rights reserved.
    L Li, GJ Clarkson, DJ Evans, MR Lees, SS Turner, P Scott (2011)Isomeric Fe(ii) MOFs: from a diamond-framework spin-crossover material to a 2D hard magnet., In: Chem Commun (Camb)47(47)pp. 12646-12648
    Two Fe(ii) coordination polymers formed from isomeric ligands give a diamond-like 3D network exhibiting a gradual SCO and a 2D hard magnet with a large coercive field.
    Max Attwood, Hiroki Akutsu, Lee Martin, Dyanne Cruickshank, Scott S. Turner (2019)Above room temperature spin crossover in thioamide-functionalised 2,6-bis(pyrazol-1-yl)pyridine iron(ii) complexes, In: Dalton Transactions48(1)pp. 90-98 Royal Society of Chemistry
    This work describes the synthesis of two novel functionalised 2,6-bis(pyrazol-1-yl)pyridine (bpp) ligands, namely 2,6-bis(pyrazol-1-yl)pyridine-4-carbothioamide (bppCSNH2) and N-methyl-2,6-bis(pyrazol-1-yl)pyridine-4-carbothioamide (bppCSNHMe). The corresponding solvated or non-solvated Fe(II) salts, [Fe(bppCSNH2)2]X2 and [Fe(bppCSNHMe)2]X2 (X = BF4− or ClO4−) were synthesised and their properties measured by SQUID magnetometry, Evans NMR, differential scanning calorimetry and single crystal X-ray diffraction. In the solid state [Fe(bppCSNH2)2]2+ salts persist in the low spin state below 350 K. The structure of [Fe(bppCSNH2)2](BF4)2·2MeNO2 shows a network of intermolecular interactions responsible for the low spin state stabilisation, relative to the prototypical [Fe(bpp)2]2+ spin crossover (SCO) salts. By contrast the complexes of bppCSNHMe both display abrupt SCO above 300 K. [Fe(bppCSNHMe)2](BF4)2·MeNO2 requires solvent loss before SCO can be observed centred at 332 K. The non-solvated [Fe(bppCSNHMe)2](ClO4)2 shows SCO centred at 325 K. Analysis of solvated and non-solvated crystal structures suggests that cooperativity is facilitated by thioamide-group interactions with neighbouring pyrazolyl and pyridyl moieties.
    A Narduzzo, AI Coldea, A Ardavan, J Singleton, L Pardi, V Bercu, A Akutsu-Sato, H Akutsu, SS Turner, P Day (2006)A spin resonance investigation of magnetism and dynamics in the charge transfer salts ß’’-(BEDT-TTF)4[(H3O)M(C2O4)3S], In: J. Low Temp. Phys142pp. 585-588
    H Akutsu, K Ishihara, J-I Yamada, S Nakatsuji, Scott Turner, Y Nakazawa (2016)A strongly polarized organic conductor, In: CRYSTENGCOMM18(42)pp. 8151-8154 ROYAL SOC CHEMISTRY
    The electrically conducting salt -(BEDT-TTF)2(PO-CON(CH3)CH2SO3)·3H2O crystallized in the polar space group, Pna21. 2D conducting BEDT-TTF layers and anion layers alternate along the crystallographic c axis. In the crystal, permanent dipoles of all anions point along the c axis, providing a net crystal dipole moment.
    H Akutsu, Y Maruyama, J-I Yamada, S Nakatsuji, SS Turner (2011)A new BEDT-TTF-based organic metal with an anionic weak acceptor 2-sulfo-1,4-benzoquinone, In: Synthetic Metals161(21-22)pp. 2339-2343
    H Akutsu, R Ohnishi, J-I Yamada, S Nakatsuji, SS Turner (2007)Novel bis(ethylenedithio)tetrathiafulvalene-based organic conductor with 1,1 '-ferrocenedisulfonate, In: INORGANIC CHEMISTRY46(21)pp. 8472-8474 AMER CHEMICAL SOC
    2,6-Bis(pyrazol-1-yl)pyridine (L1) and 2,2:6′,2″-terpyridine (L2) are popular ligands for use in a wide range of applications in coordination chemistry. Both ligands are capable of forming metal complexes with highly interesting and potentially exploitable properties: luminescence, catalytic redox activity and magnetic spin crossover (SCO). SCO materials have received attention because of the potential for incorporation into commercially relevant technologies such as sensors and information storage media. This review explores the potential of ‘back to back’ L1 SCO polymers using reported examples, and looks towards the larger L2 chemical library, covering the coordination chemistry with a focus on magnetic properties. In principle, polymeric coordination materials are easier to process and may offer an easier route to tuning properties that are dependent on the electronic environment. It is the intention of this review to highlight the potential of these materials, with the goal of promoting the development of multifunctional SCO hybrids.
    H Akutsu, J-I Yamada, S Nakatsuji, SS Turner (2013)Structures and properties of a BEDT-TTF-based organic charge transfer salt and the zwitterion of ferrocenesulfonate, In: DALTON TRANSACTIONS42(46)pp. 16351-16354 ROYAL SOC CHEMISTRY
    H Akutsu, J-I Yamada, S Nakatsuji, SS Turner (2007)An anionic weak acceptor 2-aminomethylsulfo-3,5,6-trichloro-1, 4-benzoquinone and its BEDT-TTF-based charge-transfer salts, In: SOLID STATE COMMUNICATIONS144(3-4)pp. 144-147 PERGAMON-ELSEVIER SCIENCE LTD
    We have prepared two dmit-based salts with a stable organic radical-substituted ammonium cation, (PO-CONH-C2H4N(CH3)3)[Ni(dmit)2]2·CH3CN and (PO-CONH-C2H4N(CH3)3)[Pd(dmit)2]2 where PO is 2,2,5,5-Tetramethyl-3-pyrrolin-1-oxyl and dmit is 2-Thioxo-1,3-dithiol-4,5-dithiolate. The salts are not isostructural but have similar structural features in the anion and cation packing arrangements. The acceptor layers of both salts consist of tetramers, which gather to form 2D conducting layers. Magnetic susceptibility measurements indicate that the Ni salt is a Mott insulator and the Pd salt is a band insulator, which has been confirmed by band structure calculations. The cationic layers of both salts have a previously unreported polar structure, in which the cation dipoles order as ➚➘➚➘ along the acceptors stacking direction to provide dipole moments. The dipole moments of nearest neighbor cation layers are inverted in both salts, indicating no net dipole moments for the whole crystals. The magnetic network of the [Ni(dmit)2] layer of the Ni salt is two-dimensional so that the magnetic susceptibility would be expected to obey the 1D or 2D Heisenberg model that has a broad maximum around T ≈ θ. However, the magnetic susceptibility after subtraction of the contribution from the PO radical has no broad maximum. Instead, it shows Curie–Weiss behavior with C = 0.378 emu·K/mol and θ = −35.8 K. The magnetic susceptibility of the Pd salt obeys a Curie–Weiss model with C = 0.329 emu·K·mol−1 and θ = −0.88 K.
    H Akutsu, J-I Yamada, S Nakatsuji, SS Turner (2013)One-dimensional anionic metal-organic chain generated from(Tetraphenylphosphonium)benzoquinonediiminedisulfonate and CuI, In: X-ray Structure Analysis Online29(10)pp. 41-42
    The title compound, (CHP)(CHNOS)CuI.0.34HO, was obtained by the slow evaporation of a solvent from an acetonitrile solution containing a mixture of (PPh)N,N'-disulfobenzoquinonediimine and CuI. The structure consists of a one-dimensional metal-organic framework of the dianion and CuI. The anionic chains are surrounded by relatively large counter-cations, and are thus well isolated from each other.
    Hiroki Akutsu, Keita Ishihara, Soich Ito, Fumiyoshi Nishiyama, Jun-ichi Yamada, Shin'ichi Nakatsuji, Scott Turner, Yasuhiro Nakazawa (2017)Anion polarity-induced self-doping in a purely organic paramagnetic conductor, α′-α′-(BEDT-TTF)2(PO-CONH- m -C6H4SO3)·H2O where BEDT-TTF is bis(ethylenedithio)tetrathiafulvalene and PO is the radical 2,2,5,5-Tetramethyl-3-pyrrolin-1-oxyl, In: Polyhedron136pp. 23-29 Elsevier
    A new BEDT-TTF-based salt with an organic free radical, α′-α′-(BEDT-TTF)2(PO-CONH-m-C6H4SO3)·H2O, has been prepared. The crystal structure consists of alternating donor and anion/water layers propagated along the c axis. The anisotropic radical anions form a head-to-head arrangement, which provides a permanent dipole moment. The effect on the nearest donor layer has been estimated to be 4.0 V. The salt has two crystallographically independent donor layers (A and B), one of which (A) is surrounded by the negative ends of the anion layer dipole whereas the B layers are bordered by the positive ends of the dipole. This structural feature suggests that layers A and B have different Fermi levels. To eliminate the imbalance, self-doping occurs whereby electron density is transferred from layer A to B. The temperature dependence of the magnetic susceptibility has 11.1% of extra Curie spins, from which a doping ratio of 12.7% has been estimated.
    H Akutsu, A Akutsu-Sato, SS Turner, D Le Pevelen, P Day, V Laukhin, AK Klehe, J Singleton, DA Tocher, MR Probert, JA Howard (2002)Effect of included guest molecules on the normal state conductivity and superconductivity of beta''-(ET)(4)[(H(3)O)Ga(C(2)O(4))(3)].G (G = pyridine, nitrobenzene)., In: J Am Chem Soc124(42)pp. 12430-12431
    Normal state conductivity and superconductivity together with bulk magnetic susceptibility and magnetization measurements have been measured for two molecular charge-transfer salts: beta' '-(ET)4[(H3O)Ga(C2O4)3]G (ET = bis(ethylenedithio)tetrathiafulvalene, G = pyridine for compound I and nitrobenzene for compound II). With the exception of the included guest molecules (G) the crystal structures are almost identical. Both show minima in their electrical transport at 130 K for I and at 160 K for II, but at lower temperatures their behaviors differ markedly. The resistance of I reaches a maximum at 50 K with a further small peak at 2 K and possible superconductivity only below 2 K, whereas that of II increases continuously down to 7.5 K, where an abrupt transition to a superconducting state occurs.
    NP Chmel, LEN Allan, JM Becker, GJ Clarkson, SS Turner, P Scott (2011)TTF salts of optically pure cobalt pyridine amidates; detection of soluble assemblies with stoichiometry corresponding to the solid state, In: DALTON TRANSACTIONS40(8)pp. 1722-1731 ROYAL SOC CHEMISTRY
    A Narduzzo, A Ardavan, J Singleton, L Pardi, V Bercu, A Akutsu-Sato, H Akutsu, SS Turner, P Day (2004)Electron spin resonance studies of the organic superconductor β″-(BEDT-TTF)4[(H3O)Fe(C2O 4)3]C6H5CN, In: Journal De Physique. IV : JP114pp. 347-349
    We applied magneto-optical techniques to investigate the electron spin resonance (ESR) spectra of single crystal and powder samples of the organic superconductor β″-(BEDT- TTF)4[(H3O)Fe (C 2O4]C6H5CN. Data were obtained in magnetic fields up to 10 Tesla using both cylindrical and rectangular resonators at 55, 63 and 72 GHz and transmission measurements at 95 and 190 GHz with field modulation. Analysis of the high field-high frequency ESR lines for different field orientations and temperatures allows the determination of the g-value anisotropy and the zero-field splitting parameters for the Fe3+ ions (S = 5/2), showing that they occupy a site with distorted octahedral symmetry. The temperature and frequency dependences of the magneto-optical spectra are used to identify the nature of the interaction between localised Fe spins and between the local moments and the delocalised carriers. © EDP Sciences,.
    S Rashid, SS Turner, D Le Pevelen, P Day, ME Light, MB Hursthouse, S Firth, RJH Clark (2001)β″-(BEDT-TTF)[(HO)Cr(CO )]CHCl: Effect of included solvent on the structure and properties of a conducting molecular charge-transfer salt, In: Inorganic Chemistry40(20)pp. 5304-5306 American Chemical Society
    The new charge-transfer salt β″-(BEDT-TTF)[(HO)Cr(CO )]S, where BEDT-TTF = bis-(ethylenedithio)tetrathiafulvalene and S = CHCl has a broad metal-insulator transition at approximately 150 K. This differs from similar salts in the BEDT-TTF tris(oxalato) metalate series, notably the superconducting materials with S = PhCN and the salt with S = CHN, which has a sharp metal-insulator transition.
    G Rombaut, SS Turner, D Le Pévelen, C Mathonière, P Day, K Prout (2001)An unusual phase transition in the crystal structure and physical properties of (TTF)[MO(CN)]·4HO, where TTF = tetrathiafulvalene, In: Journal of the Chemical Society, Dalton Transactions(22)pp. 3244-3249
    At 270 K, the charge transfer salt(TTF)[Mo(CN)]·4H O,I, crystallizes in the triclinic space group P1̄ with a = 9.9094(2), b = 10.6781(2), c = 23.6086(7) Å, a = 75.7910(8), β = 88.6010(9), γ = 78.5250(8)°, V = 2372.5(1) Å and Z = 2. At 120 K, the space group is unchanged with a = 9.7990(7), b = 10.6630(5), c = 22.9940(2) Å, a = 79.981(4), β = 89.798(4), γ = 79.013(4)°, V = 2321.5 Å and Z = 2. On comparing the two sets of data, we see significant changes in the cell parameters, most notably in the angle a. Variable temperature crystallographic studies indicate a first order phase transition accompanied by hysteresis, which corresponds to a change in the transport properties.I is a semiconductor and the high temperature activation energy of 0.06 eV changes sharply to 0.15 eV below 236 K. Bulk magnetic susceptibility and ESR measurements indicate that the TTF molecules are antiferromagnetically coupled. The temperature dependence of the EPR spectrum changes from 300-200 K, in approximate agreement with the transport and structural results. The optical spectrum of (TTF)[Mo(CN)]·4HO consists of several broad bands assigned to TTF charged molecules, to [Mo(CN)] and to charge transfer from the donors to the acceptor in the near infra-red range. Preliminary magnetic susceptibility measurements under light irradiation with a multi-line (752.5-799.3 nm) laser were also performed, but no photomagnetic effect was noted.
    M Mas-Torrent, J Vidal-Gancedo, J Veciana, C Rovira, SS Turner, P Day, K Wurst (2003)New molecular charge-transfer salts of TM-TTF and BMDT-TTF with thiocyanate and selenocyanate complex anions [TMTTF = tetramethyltetrathiafulvalene; BMDT-TTF = bis(methylenedithio)tetrathiafulvalene], In: European Journal of Inorganic Chemistry(4)pp. 720-725
    Three new charge-transfer salts of tetrathiafulvalene (TTF)-based donors with thiocyanato- or selenocyanato-metal complex anions have been synthesised. The salts isolated were [BMDT-TTF][Cr(NCS)] (1), [TM-TTF][Cr(NCS)]·2CHCN (2) and [TM-TTF][Cr(NCSe)]·2CHCN (3) [BMDT-TTF = bis-(methylenedithio)tetrathiafulvalene and TM-TTF = tetramethyltetrathiafulvalene]. Single crystals of compound 1 crystallise in the monoclinic C2/c space group with a = 37.286(3), b= 10.0539(6), c= 21.069(2) Å, β = 124.348(4)°, V = 6520.9(9) Å and Z = 4. Compound 3 was also suitable for an X-ray diffraction study, however the anionic part, [Cr(NCSe)] was highly disordered and the best solution gave a final R factor of 16.4%. A solution was found for the monoclinic space groupo C2/m with a = 113.787(3), b= 19.507(3), c = 14.735(5) Å, β = 102.90(3)°, V = 3862.9(17) Å and Z = 2. For compound 1 there are several S ⋯ S close atomic contacts between the donors and acceptors, but there is no discernible magnetic exchange between ions. Such an interaction was previously observed in related salts such as [TTF][Cr(NCS)(phenanthroline)] and [donor] [M(NCS)(isoquinoline)] [M = Cr, Fe and donor = TTF, BEDT-TTF or TM-TTF (tetramethyltetrathiafulvalene)]. Compounds 1 to 3 are all paramagnetic semiconductors in which the magnetic susceptibility is dominated by the Cr-containing anions. The structure-function relationship, along with a comparison with related compounds, indicates that there is no long-range magnetic order because there are no π-stacking interactions between donor and acceptor; these types of interactions are seen in all of the bulk magnets of this type in which the donor spin is magnetically coupled to the anion. © Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003.
    L Li, Z Liu, D Liao, Z Jiang, S Yan, SS Turner (2003)The first one-dimensional copper(II)-radical system with alternating double end-on and end-to-end azido bridges, In: New Journal of Chemistry27(4)pp. 752-755
    A novel one-dimensional copper(II)-radical complex [Cu(NITmPy)(N)(CHOH)] [NITmPy = 2-(3′-pyridyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide] has been synthesized and structurally characterized. The structure consists of neutral chains of copper(II) ions alternatively bridged by double symmetric end-on and asymmetric end-to-end azide groups. The NITmPy radical ligand coordinates to the copper(II) ions through the nitrogen atom of the pyridyl ring. The magnetic properties were investigated in the temperature range 5-300 K. The complex exhibits ferromagnetic interactions between the copper(II) ions through the end-on and end-to-end azido bridging ligands, and between the copper(II) ion and NITmPy radical. The magnetic behavior is discussed with reference to the crystal structure.
    A Akutsu-Sato, H Akutsu, J Yamada, S Nakatsuji, SS Turner, P Day (2007)Suppression of superconductivity in a molecular charge transfer salt by changing guest molecule: β″-(BEDT-TTF)[(H O)Fe(CO)](CH CN)(CHN), In: Journal of Materials Chemistry17(24)pp. 2497-2499
    SQUID magnetometry and transport measurements combined with crystal structure refinement have been used to examine the variation in superconducting properties (T and Meissner fraction) in the molecular superconductor β″-(BEDT-TTF)[(HO)Fe(CO )]·CHCN on replacing the CHCN guest molecule with pyridine (CH N). Up to approximately 65% pyridine substitution there is only a small decrease in T and Meissner fraction but above that the superconductivity is suppressed. © The Royal Society of Chemistry 2007.
    H Akutsu, S Yamashita, J-I Yamada, S Nakatsuji, Y Hosokoshi, SS Turner (2011)A Purely Organic Paramagnetic Metal, kappa-beta ''-(BEDT-TTF)(2)(PO-CONHC2H4SO3), Where PO=2,2,5,5-Tetramethyl-3-pyrrolin-1-oxyl Free Radical, In: CHEMISTRY OF MATERIALS23(3)pp. 762-764 AMER CHEMICAL SOC
    SS Turner, D Le Pévelen, P Day, K Prout (2002)Synthesis, crystal structures and physical properties of TTF-based conducting charge transfer salts with anions containing selenocyanate ligands, In: Journal of Solid State Chemistry168(2)pp. 573-581
    Three new charge transfer salts of tetrathiafulvalene (TTF)-based donors with selenocyanate-metal complex anions have been synthesized. The salts have been characterized as BEDT-TTF[Cr(NCSe)]·CHCl , II, TTF[Cr(NCSe)phen], III and BEDT-TTF[Cr(NCSe)phen]·CHCl , IV, where phen = 1,10′-phenanthroline and BEDT-TTF = bis(ethylenedithio)tetrathiafulvalene. At 120 K, II crystallizes in the P2/m space group with a = 10.454(1), b = 31.990(1), c = 12.339(1) Å, β = 113.163(2)°, V = 3793.8 Å, Z = 4 and at 240 K in the same space group with a = 10.530(1), b = 32.122(1), c = 12.396(1) Å, β = 113.186(3)°, V = 3854.2 Å, Z = 4. At 240 K III crystallizes in the C2/c space group, a = 38.9272(5), b = 11.2992(1), c = 15.2540(3) Å, β = 106.8877(6)°, V = 6420.1 Å, Z = 8. The structure of IV has been solved in the P1̄ space group with a = 8.7629(3), b = 11.7977(4), c = 26.6031(9), α = 81.697(2), β = 87.858(3), γ = 74.8471(14), V = 2626.8 Å, Z = 2. All of the salts have numerous S⋯Se close atomic contacts between donors and acceptors but there is no magnetic exchange between ions, as previously seen in closely related salts such as TTF[Cr(NCS)phen] and (donor)[M(NCS)(isoquinoline)], where M = Cr, Fe and donor = TTF, BEDT-TTF or TMTTF (tetramethyltetrathiafulvalene). Indeed, II and IV are paramagnetic semiconductors whereas IlI is a paramagnetic insulator. The absence of long-range magnetic order is discussed in terms of structure-function relations since there are no π-stacking interactions between donor and acceptor, which are seen in all of the bulk magnets of this type where the donor spin is magnetically coupled to the anion. The synthesis and crystal structure of the starting material, [(CH)N][Cr(NCSe) ], I, is also reported; it crystallizes in the P1̄ space group with a = 12.220(1), b = 12.814(1), c = 13.008(1) Å, α = 99.608(6), β = 114.028(5), γ = 92.637(6)°, V = 1819.5 Å, Z = 2. © 2002 Elsevier Science (USA).
    Many molecular charge transfer salts with organo-chalcogen donors and transition-metal complex anions have been synthesised in recent years in an effort to find lattices that combine conductivity with long range magnetic order, but in most cases interaction between the donor and anion sublattices is very weak. We have approached this issue by selecting anions that contain S or Se atoms capable of forming close non-bonding contacts with the donor molecules, and which also contain aromatic rings to form π-π contacts. In this way new ferrimagnets have been synthesised and characterised, with general formula D[M(NCX)B] where D is TTF or BEDT-TTF; M = Cr, Fe; X = S, Se; B = 1,10-phenantholine, isoquinoline. We have demonstrated that cation-anion S⋯S and π⋯π contacts are necessary. © 2002 Elsevier Science B.V. All rights reserved.
    H Akutsu, T Sasai, J Yamada, S Nakatsuji, SS Turner (2010)New anionic acceptors Br(2)XQNHCH(2)SO(3)(-) [X=Br, BryCl1-y (y approximate to 0.5), and Cl; Q=1,4-benzoquinone) and their charge-transfer salts, In: PHYSICA B-CONDENSED MATTER405(11)pp. S2-S5 ELSEVIER SCIENCE BV
    We have prepared new organic anionic acceptors Br(2)XQNHCH(2)SO(3)(-) (2 X=Br 3 X=BryCl1-y (y approximate to 0 5) 4 X=Cl Q=1 4-benzoquinone) that possess both an electron acceptor part (1 4-benzoquinone) and an anionic part (sulfonate) The reduction potentials of the PPh4 salts of 2 3 and 4 are -0 45 -0 45 and 0 46 V (vs SCE in CH3CN) respectively The results indicate that they are weaker acceptors than chloranil (-0 13 V) and bromanil (-0 12 V) Each anionic acceptor (AA) provided two BEDT-TTF salts beta-(ET)(5)(AA)(2) DCE zH(2)O and -(ET)(2)(AA) CH3OH (AA=2 3 or 4 z=2 0 97 3 0 83 and 4 0 40) The structures and transport properties of the salts are reported (C) 2009 Elsevier B V All rights reserved
    H Akutsu, JI Yamada, S Nakatsuji, SS Turner (2014)Crystal structure of PPh4[Fe(NO)2Cl2], In: X-ray Structure Analysis Online30(10)pp. 49-50
    © The Japan Society for Analytical Chemistry.The title compound, (C24H20P)(FeN2O2Cl2), was prepared by adapting of literature methods. It crystallizes in the tetragonal space group P4. The structure consists of one P(C6H5)4 cation and one Fe(NO)2Cl2 anion. The anion has one ordered NO group and one ordered Cl ligand. The other two ligands are disordered, such that one half of NO and a half of Cl are located at each position.
    K Furuta, H Akutsu, J Yamada, S Nakatsuji, SS Turner (2006)The first organic molecule-based metal containing ferrocene, In: JOURNAL OF MATERIALS CHEMISTRY16(16)pp. 1504-1506 ROYAL SOC CHEMISTRY
    Max Julian David Attwood, Hiroki Akutsu, Lee Martin, Dyanne Cruickshank, Scott S Turner (2018)Above Room Temperature Spin Crossover in Thioamide-Functionalised 2,6-bis(pyrazol-1-yl)pyridine Iron(II) Complexes, In: Dalton Transactions(48)pp. 90-98 Royal Society of Chemistry
    This work describes the synthesis of two novel functionalised 2,6-bis(pyrazol-1-yl)pyridine (bpp) ligands, namely 2,6-bis(pyrazol-1-yl)pyridine-4-carbothioamide (bppCSNH2) and N-methyl-2,6-bis(pyrazol-1-yl)pyridine-4-carbothioamide (bppCSNHMe). The corresponding solvated or non-solvated Fe(II) salts, [Fe(bppCSNH2)2]X2 and [Fe(bppCSNHMe)2]X2 (X = BF4- or ClO4-) were synthesised and their properties measured by SQUID magnetometry, Evans NMR, differential scanning calorimetry and single crystal X-ray diffraction. In the solid state [Fe(bppCSNH2)2]2+ salts persist in the low spin state below 350 K. The structure of [Fe(bppCSNH2)2](BF4)2.2MeNO2 shows a network of intermolecular interactions responsible for the low spin state stabilisation, relative to the prototypical [Fe(bpp)2]2+ spin crossover (SCO) salts. By contrast the complexes of bppCSNHMe both display abrupt SCO above 300 K. [Fe(bppCSNHMe)2](BF4)2.MeNO2 requires solvent loss before SCO can be observed centred at 332 K. The non-solvated [Fe(bppCSNHMe)2](ClO4)2 shows SCO centred at 325 K. Analysis of solvated and non-solvated crystal structures suggests that cooperativity is facilitated by thioamide-group interactions with neighbouring pyrazolyl and pyridyl moieties.
    N Saygili, RJ Brown, R Hoelzl, ER Mageean, T Ozturk, M Pilkington, L Vorwerg, JD Wallis, P Day, SS Turner, P Kathirgamanathan, MMB Qayyum (2001)Functionalised organosulfur donor molecules: Synthesis of racemic hydroxymethyl-, alkoxymethyl- and dialkoxymethyl-bis(ethylenedithio)tetrathiafulvalenes, In: Tetrahedron57(23)pp. 5015-5026 Elevier
    Short synthetic routes to racemic derivatives of bis(ethylenedithio)tetrathiafulvalene carrying one hydroxymethyl (HMET), alkoxymethyl or dialkoxymethyl side chain are reported along with cyclic voltammetry measurements and conversion of HMET to (2:1) radical cation salts. © 2001 Elsevier Science Ltd.
    T Yamamoto, Y Nakazawa, R Kato, H Yamamoto, K Yakushi, H Akutsu, AS Akustu, A Kawamoto, SS Turner, P Dayg (2010)Charge fluctuation of the superconducting molecular crystals, In: Physica B: Condensed Matter405(11 SUP)
    In recent years, concern has been raised about the charge fluctuation of the superconducting transition in the loosely dimerized molecular conductors. Not only the observation of the charge fluctuation is of considerably important but also the understanding of the mechanism of the fluctuation. We have observed degree of charge fluctuation of several β''-type ET salts. The β''-type ET salt is one of the best model compounds because the direction of the largest inter-site Coulomb interaction is perpendicular to that of the largest transfer integral. This structural property allows us to examine the role of inter-site Coulomb interaction from the viewpoint of the inter-molecular distance. The difference in the molecular charges between the charge rich site and the charge poor sites, Δρ, is correlated with the conducting behavior; the superconducting materials have the small but finite Δρ, whereas Δρ of the insulating (metallic) materials is large (almost zero). After the analysis of the configuration in the inter-molecular distances, we have found that the degree of fluctuation, Δρ, is attributed to the number of the most stable charge distribution(s), NS, and the number of the energy levels of the allowed charge distribution, NA. The superconducting materials belong to the condition of N ≥2 and N ge;2. Indeed, this condition contributes to the fluctuation of the molecular charges. © 2010 Elsevier B.V. All rights reserved.
    H Akutsu, J-I Yamada, S Nakatsuji, SS Turner (2009)A new anionic acceptor, 2-sulfo-3,5,6-trichloro-1,4-benzoquinone and its charge-transfer salts, In: CRYSTENGCOMM11(12)pp. 2588-2592 ROYAL SOC CHEMISTRY
    S Rashid, SS Turner, P Day, ME Light, MB Hursthouse, S Firth, RJH Clark (2001)The first molecular charge transfer salt containing proton channels, In: Chemical Communications(16)pp. 1462-1463 Royal Society of Chemistry
    We report the first molecular charge transfer salt containing channels of H O /H O within its lattice; it is formulated β″-(BEDT-TTF) [(H O)Cr(C O ) ] [(H O) (18-crown-6)]·5H O [BEDT-TTF = bis(ethylenedithio)tetrathiafulvalene], deduced from the crystal structure and C=C and C-S bond lengths and Raman stretching frequencies.
    H Akutsu, R Hashimoto, J Yamada, S Nakatsuji, Scott Turner, Y Nakazawa (2018)Structure and properties of a BEDT-TTF-based organic conductor with a ferrocene-based magnetic anion octamethylferrocenedisulfonate, In: European Journal of Inorganic Chemistry2018(27)pp. 3249-3252 Wiley
    The structure and properties of a new semiconducting BEDT-TTF-based charge-transfer salt containing the magnetic monoanion octamethylferrocenedisulfonate (–O3SC5( CH3)4Fe+C5(CH3)4-SO3 – (ofds)), -(BEDT-TTF)5(ofds)2 is described (BEDT-TTF = bis(ethylenedithio)tetrathiafulvalene). The salt is a semiconductor with RT = 5.6  103 ·cm and Ea = 0.11 eV. There are two types of spins not only on the ferrocenyl parts but also the 2D donor layers. The former and latter spins obey Curie-Weiss (C = 0.721 emu K mol-1and  = -5.5 K) and 2D Heisenberg (J2DH = - 80.3 K) models, respectively.
    NP Chmel, SE Howson, LEN Allan, J Barker, GJ Clarkson, SS Turner, P Scott (2010)Organic-soluble optically pure anionic metal complexes PPh(4)[M(III)(S,S-EDDS)]center dot 2H(2)O (M = Fe, Co, Cr), In: DALTON TRANSACTIONS39(11)pp. 2919-2927 ROYAL SOC CHEMISTRY
    This paper reports the preparation, X-ray crystal structure, conducting and magnetic properties of α-(BEDT-TTF)]Fe(phen) (NCS)[ (1) [BEDT-TTF = bis(ethylenedithio)tetrathiafulvalene, phen = 1,10-phenanthroline] together with the crystal structure of (BEDT-TTF)]Cr (isoq)(NCS)[ (2) (isoq = isoquinoline) for which the physical properties have been reported previously. Compound 1 crystallizes in the triclinic space group P1 (no. 2), a = 12.1528(1), b = 16.8269(3), c = 27.0703(4) Å, α = 95.726(1), β = 95.834(1), γ = 108.080(1)°, Z = 4, R = 0.0610 for 9764 reflections with I > 2σ(I); 2 crystallizes in the monoclinic space group P2/c (no. 14), a =10.623(5), b = 14.656(8), c = 12.701(7) Å, β = 100.19(2)°, Z = 2, R = 0.0737 for 2747 reflections with I > 2σ(I). The magnetic and transport properties have shown that compound 1 is a paramagnetic semiconductor with σ = 2.2 × 10 Ω cm. © 2002 The Royal Society of Chemistry.
    AI Coldea, AF Bangura, A Ardavan, J Singleton, A Akutsu-Sato, H Akutsu, SS Turner, P Day (2004)Fermi-surface topology and the effects of intrinsic disorder in a class of charge-transfer salts containing magnetic ions: β″-(BEDT-TTF) [HO)M(CO)]Y (M=Ga, Cr, Fe; Y=CHN), In: Physical Review B - Condensed Matter and Materials Physics69(8)pp. 851121-8511211
    We report high-field magnetotransport measurements on β″ -(BEDT-TTF)[(HO)M(CO) ]Y, where M =Ga, Cr, and Fe and Y=CHN. We observe similar Shubnikov-de Haas oscillations in all compounds, attributable to four quasi-two-dimensional Fermi-surface pockets, the largest of which corresponds to a cross-sectional area ≈8.5% of the Brillouin zone. The cross-sectional areas of the pockets are in agreement with the expectations for a compensated semimetal, and the corresponding effective masses are ∼m , rather small compared to those of other BEDT-TTF salts. Apart from the case of the smallest Fermi-surface pocket, varying the M ion seems to have little effect on the overall Fermi-surface topology or on the effective masses. Despite the fact that all samples show quantum oscillations at low temperatures, indicative of Fermi liquid behavior, the sample and temperature dependence of the interlayer resistivity suggest that these systems are intrinsically inhomogeneous. It is thought that intrinsic tendency to disorder in the anions and/or the ethylene groups of the BEDT-TTF molecules leads to the coexistence of insulating and metallic states at low temperatures. A notional phase diagram is given for the general family of β″-(BEDT-TTF) [(HO)M(CO)]Y salts.
    A Akutsu-Sato, A Kobayashi, T Mori, H Akutsu, J Yamada, S Nakatsuji, SS Turner, P Day, DA Tocher, ME Light, MB Hurstho (2005)Structures and physical properties of new β′-BEDT-TTF tris-oxalatometallate (III) salts containing chlorobenzene and halomethane guest molecules, In: Synthetic Metals152(1-3)pp. 373-376
    We report the structures and physical properties of new β′-(BEDT-TTF)[Fe(oxalate)]·G salts where A = HO, G = PhCl; A = Rb G = Pyridine. The structure of the PhCl salt is isomorphous with β′-(BEDT-TTF)[(HO)M(oxalate)] with other guest molecules. PhCl is ordered in die hexagonal pockets formed by the [(HO)Fe(oxalate)] layer. The electrical conductivity is metallic down to 100 K, below which the resistivity increases with decreasing temperature. The specific conductivity at room temperature is about 10 S/cm. We also report the salt β′-(BEDT-TTF) [RbFe(oxalate)]·Pyridine where Rb replaces HO. The electrical resistivity shows metallic behavior down to 100 K. and turns up gradually to a maximum at 65 K below which the system re-enters the metallic state down to liquid helium temperature. Neither salt shows superconductivity down to 2 K. In addition, other new β′-(BEDT-TTF)[(HO)M(oxalate) ]·salts with M = Cr, Ga, Fe; G = CHCl , CHClBr, CHBr are also reported. © 2005 Elsevier B.V. All rights reserved.
    EZ Kurmaev, VR Galakhov, A Moewes, S Shimada, K Endo, SS Turner, P Day, RN Lyubovskaya, DL Ederer, M Iwami (2000)Electronic structure of molecular superconductors containing paramagnetic 3d ions, In: Physical Review B - Condensed Matter and Materials Physics62(17)pp. 11380-11383
    The results of x-ray fluorescence measurements of the molecular superconductors (ET)[(HO)Fe(CO) ]·CHCN (T = 8.5 K) and (ET)[(HO)Cr(CO) ]·CHCN (T ∼ 6 K) and molecular conductor (ET)[(HO)Fe(CO) ]·CHN containing paramagnetic 3d ions are presented. The following transition of the x-ray emission valence spectra are monitored: C K α, N K α (2p→1s transition) and Fe L, Cr L (3d4s→2p transition). It is found that the electronic structure of the solvents (benzonitrile, pyridine) that occupy the hexagonal cavities formed by the anionic layer is close to that of the neutral molecule. The ratio of the emission intensities of the peaks L to L for Fe and Cr is found to be 2.8-3.1 times higher for (ET)[(HO)Fe(CO) ]·CHCN and (ET)[(HO)Cr(CO) ]·CHCN than for pure metals. This indicates that the paramagnetic 3d ions are situated in highly insulating anionic layers. We did not find any changes in the C K α emission for different solvent molecules.
    A Narduzzo, A Ardavan, AI Coldea, J Singleton, A Akutsu-Sato, H Akutsu, SS Turner, P Day (2003)Millimetre-wave response of the novel organic superconductors β″-ET[(HO)M(CO)].S (M=Fe, S= CHCN and CHNO), In: Synthetic Metals137(1-3)pp. 1225-1226
    The millimeter-wave response of the novel organic superconductors was studied. The magneto-optical response of the two samples containing Fe ions and the host solvents benzonitrile and nitrobenzene. The angle dependence of the electron paramagnetic resonance (EPR) spectra and the anisotropy of the g-factors for the two materials were presented. The angle of dependence of the absorption spectra at 1.4 K for the two samples were compared.
    AI Coldea, AF Bangura, A Ardavan, J Singleton, A Akutsu-Sato, H Akutsu, SS Turner, P Day (2004)Fermiology of new charge-transfer salts, β″-(BEDT-TTF) 4[(H3O)M(C2O4)3]-solvent where M = Ga, Cr and Fe, In: Journal De Physique. IV : JP114pp. 205-209
    We report high-field magnetotransport measurements on β″-(BEDT- TTF)4[(H3O)M(C2O4) 3]· solvent, where M=Ga3+, Cr3+ and Fe3+ and solvent=C5H5N. In spite of their differing transition metal-ions, M, the three compounds exhibit similar magnetic quantum oscillation spectra superimposed on a positive magnetoresistance. At least four independent quantum oscillation frequencies have been identified, corresponding to two different hole and electron pockets of the Fermi surface which follow the rules of a compensated metal. Observation of the small pockets could be the result of the Fermi surface reconstruction induced by a possible density wave. The effective masses are very similar for different samples and for different pockets range between meff ≈ 0.5-1.1 me whereas the Dingle temperatures varies between TD ≈ 1.4-4 K. At low temperature, the longitudinal magnetoresistance violates Kohler's rule, suggesting that the interlayer transport in these quasi-2D systems cannot be related to a single scattering time and that the disorder plays an important role. © EDP Sciences.
    S Rashid, SS Turner, P Day, ME Light, MB Hursthouse, P Guionneau (2001)Novel charge transfer salts of BEDT-TTF with metal oxalate counterions, In: Synthetic Metals120(1-3)pp. 985-986 Elsevier
    The preparation, crystal structures and properties of three new BEDT-TTF, bis(ethylenedithio)tetrathiafulvalene, (ET for short), charge transfer salts β″(ET).[(HO)Cr(C O)].CHNOI, β″(ET).[(HO)Fe(C O)].CHNO II and (ET).[Fe(CO)] III are reported. The structures of I and II consist of alternating layers of ET and an approximately hexagonal network formed by HO and the metal with the solvent molecule, CHNO, occupying hexagonal cavities in the anion layer. Both CHNO salts are superconducting, the iron salt having a T of 6.2 K and the chromium salt having a T of 5.8 K. The structure of (ET)[Fe(CO)] consists of an iron oxalate bridged dimer, (Fe-Fe distance 5.472 Å), interspersed with ET in a "checker board" arrangement. It is monoclinic and crystallises in the P2/n space group. At 150 K a = 16.8068 (3) Å, b = 10.9556 (2) Å, c = 19.4109 (3) Å, β = 102.1593 (9)° and V = 3493.92 (10) Å. Squid measurements show short range antiferromagnetic ordering.
    RJ Darton, SS Turner, J Sloan, MR Lees, RI Walton (2010)Hydrothermal Synthesis of a B-Site Magnetic Ruthenate Pyrochlore, In: CRYSTAL GROWTH & DESIGN10(8)pp. 3819-3823 AMER CHEMICAL SOC
    SS Turner, C Michaut, S Durot, P Day, T Elbrich, MB Hursthouse (2000)TTF based charge transfer salts of [M(NCS)(CHN)] where M = Cr, Fe and CHN = isoquinoline; observation of bulk ferrimagnetic order, In: Journal of the Chemical Society, Dalton Transactions(6)pp. 905-909
    Three new charge transfer salts of BEDT-TTF and TTF with the counter ions [M(NCS)4(C9H7N)J~ (M = Cr, Fe; C9H7N = isoquinoline) are described. The materials are prepared by standard electrocrystallisation techniques. The nature of the anion is verified in the crystal structure of the salt [C9H8N][Cr(NCS)4(C9H7N)]-C,2H24O6-H2O which is used as the electrolyte when M = Cr. All of the charge transfer salts display long range ferrimagnetic order originating from the interaction between M (5=3/2 or 5= 5/2) and the donor (5= 1/2). The measured critical temperatures are 4.2 K (BEDT-TTF, M = Cr), 4.5 K (BEDT-TTF, M = Fe) and 8.9 K (TTF, M = Cr). Each of the compounds also shows a modest magnetic hysteresis of 338, 18 and 75 Oe for BEDT-TTF salts of M = Cr, Fe and the TTF salt of Cr, respectively. © The Royal Society of Chemistry 2000.
    A series of new charge transfer salts of electron donors based on tetrathiafulvalene, TTF, with the anion [Cr(NCS)4(phen)]~ (phen = 1,10-phenanthroline) have been prepared. Single crystal X-ray diffraction provided structures for salts with donors TTF, TMTTF, tetramethyltetrathiafulvalene, and TMTSF, tetramethyltetraselenafulvalene. The salts were found to be [TTF][Cr(NCS)(phen)] at 293 K, [TMTTF][Cr(NCS)(phen)]-CHCl2 at 250 K and rrMTSF][Cr(NCS)(phen)]2-0.5CHCl at 293 K. For the TMTSF compound the solvent is disordered at 293 K so the structure was also solved at 120 K when the solvent becomes ordered. All of the salts have multiple S ⋯S or S ⋯Se close contacts between the anions and cations. The TTF salt is a bulk ferrimagnet with Tc = 9 K and is an insulator whereas the TMTTF salt is an antiferromagnetic (TN = 3.0 K) insulator. Both have close atomic interactions of the phen-donor n-stacking type, but the TMTTF salt also contains close anion-anion contacts and dimerised cations whereas the TTF salt consists of stacks of alternating cations and anions. The TMTSF salt is a paramagnetic semiconductor and does not display n stacking but has close inter-donor Se ⋯Se contacts and isolated anions which afford the magnetic and transport properties. © The Royal Society of Chemistry 2000.
    Two new charge transfer salts of BEDT-TTF, bis (ethylenedithio) tetrathiafulvalene, with thiocyanato-metal complex anions have been synthesized and characterized as (BEDT-TTF)[Fe(NCS)]·CHCl and (BEDT-TTF)[Cr(NCS) (bipym)]·0.15HO, where bipym=2,2′-bipyrimidine. The Fe salt, I, crystallizes in the P-1 (No. 2) space group at 150 K with a=10.629(1) Å, b=12.099(1) Å, c=16.062(2) Å, α=99.61(1)°, β=90.87(1)°, γ=112.92(1)°, and V=1868.5(6) Å. At 150 K the Cr salt, II, crystallizes in the P-1 (No. 2) space group with a=9.243(2), b=11.781(2), c=22.925(5) Å, α=93.76(3), β=101.51(3), γ=105.45(3)°, V=2339.0(8) Å, and Z=2. Both salts exhibit close S···S contacts between the anion and cation components and in II there is no π-stacking between the bipym group and the BEDT-TTF molecules. Both salts are paramagnetic with C=4.926 I and C=1.819 II with small negative Weiss constants of -0.19 and -0.26, respectively. Therefore, the S···S contacts alone do not promote correlated magnetic effects as seen in other thiocyanato salts that also contain π-stacking. Each compound is a semiconductor and has two crystallographically independent BEDT-TTF molecules for which bond length analysis give charges of +0.9±0.1/+0.6±0.1 for I and +0.3±0.1/+0.9±0.1 for II. © 2001 Academic Press.
    AF Bangura, AI Coldea, A Ardavan, J Singleton, A Akutsu-Sato, H Akutsu, SS Turner, P Day, T Yamamoto, K Yakushi (2005)Robust superconducting state in the low-quasiparticle-density organic metals β″-(BEDT-TTF)4[(H3O)M(C2O4)3]Y: Superconductivity due to proximity to a charge-ordered state, In: Physical Review B - Condensed Matter and Materials Physics72(1)
    We report magnetotransport measurements on the quasi-two-dimensional charge-transfer salts β″-(BEDT-TTF)4[(H3O)M(C2O4)3]Y, with Y=C6H5NO2 and C6H5CN using magnetic fields of up to 45 T and temperatures down to 0.5 K. A surprisingly robust superconducting state with an in-plane upper critical field Bc2 33T, comparable to the highest critical field of any BEDT-TTF superconductor, and critical temperature Tcâ 7K is observed when M=Ga and Y=C6H5NO2. The presence of magnetic M ions reduces the in-plane upper critical field to 18T for M=Cr and Y=C6H5NO2 and M=Fe and Y=C6H5CN. Prominent Shubnikov-de Haas oscillations are observed at low temperatures and high magnetic fields, showing that the superconducting salts possess Fermi surfaces with one or two small quasi-two-dimensional pockets, their total area comprising 6% of the room-temperature Brillouin zone; the quasiparticle effective masses were found to be enhanced when the ion M was magnetic (Fe or Cr). The low effective masses and quasiparticle densities, and the systematic variation of the properties of the β″-(BEDT-TTF)4[(H3O)M(C2O4)3]Y salts with unit-cell volume points to the possibility of a superconducting groundstate with a charge-fluctuation-mediated superconductivity mechanism such as that proposed by Merino and McKenzie [Phys. Rev. Lett. 87, 237002 (2001)], rather than the spin-fluctuation mechanism appropriate for the κ-(BEDT-TTF)2X salts. © 2005 The American Physical Society.
    A Akutsu-Sato, H Akutsu, SS Turner, D Le Pevelen, P Day, ME Light, MB Hursthouse, T Akutagawa, T Nakamura (2003)Structures and physical properties of BEDT-TTF salts containing channels of protons, In: Synthetic Metals135-13pp. 597-598
    Charge transfer salts with stoichiometry β″-(BEDT-TTF) [M(CO),](18-crown-6 ether)(9HO), where M= Cr, Ga or Fe and x= 2 or 3 are reported. Their structures suggest that proton migration is possible. Variable temperature resistivity measurements on the Cr salt show metallic behaviour down to 180K. Magnetic susceptibility of the Cr salt is paramagnetic down to 1.8 K. Preliminary impedance measurements suggest that the proton conductivities of the Cr and Ga salts are the order of 10 S cm at 300 K. © 2003 Elsevier Science B.V. All rights reserved.
    H Akutsu, A Akutsu-Sato, SS Turner, P Day, DA Tocher, MR Probert, JAK Howard, D Le Pevelen, A-K Klehe, J Singleton, VN Laukhin (2003)Structures and properties of new superconductors, β″-(ET)[(HO)Ga(CO) ]Sol [Sol = nitrobenzene and pyridine], In: Synthetic Metals137(1-3)pp. 1239-1240
    The title compounds containing diamagnetic Ga are superconductors. The nitrobenzene salt shows a broad metal-semiconductor transition at 160 K but becomes superconductor below 7.5 K. The Meissner volume of a powder sample at 1.8 K is estimated at 31%. The pyridine salt also has a broad upturn in resistance at 130 K, a re-entrant metallic phase below 60 K, and a resistance loss below 1.5 K. The loss vanishes with applying magnetic field, suggesting that it is also superconductor.
    H Akutsu, J-I Yamada, S Nakatsuji, A Akutsu-Sato, SS Turner, P Day, S Firth, E Canadell, RJH Clark (2004)Superstructures of donor packing arrangements in a series of molecular charge transfer salts, In: Chemical Communications10(1)pp. 18-19
    Three conducting BEDT-TTF charge-transfer salts with tri-s(oxalato) metallate anions have unit cells containing both α and β″ donor packing motifs.
    NP Chmel, GJ Clarkson, A Troisi, SS Turner, P Scott (2011)Chiral Semiconductor Phases: The Optically Pure D-3(M-III(S,S-EDDS)](2) (D = TTF, TSF) Family, In: INORGANIC CHEMISTRY50(9)pp. 4039-4046 AMER CHEMICAL SOC
    AI Coldea, AF Bangura, A Ardavan, J Singleton, A Akutsu-Sato, H Akutsu, SS Turner, P Day (2004)The role of magnetic ions on the magnetotransport properties of the charge-transfer salts β″-BEDT-TTF[(HO) M(CO)]CHN where M=Ga, Cr or Fe, In: Journal of Magnetism and Magnetic Materials272-27pp. 1062-1064
    We report high-field magnetotransport measurements on β″-BEDT- TTF[(HO)M(CO)]C HN, where M=Ga, Cr or Fe . In spite of the differing M ions, these compounds have very similar Fermi surfaces. We observe four distinct Shubnikov-de Haas frequencies, corresponding to four Fermi-surface pockets; the frequencies exhibit the additive relationship expected for a compensated semimetal. The compounds show paramagnetic behaviour and no superconductivity down to 0.5 K, in contrast to other materials of the same family with different solvent molecules. © 2003 Elsevier B.V. All rights reserved.
    SS Turner, P Day (2005)Ion-radical salts: A new type of molecular ferrimagnet, In: Journal of Materials Chemistry15(1)pp. 23-25
    Long-range ferrimagnetic order in which one magnetic sub-lattice is formed from partly-occupied p-orbitals and the other from d-orbitals can be achieved in molecular ion-radical salts where the cations are oxidised organo-chalcogen donors and the anions are 3d-metal complexes containing both N-bonded NCS and planar N-heterocyclic ligands. Overlaps between p-orbitals of the radical cations and those of the heterocycle are implicated in the cation-anion exchange pathway.
    D Le Pevelen, SS Turner, P Day, K Prout (2001)TTF based molecular magnets : Structural and physical properties of new salts involving the [Cr(NCS)(phen)] anion, In: Synthetic Metals121(1-3)pp. 1842-1843
    Our group has recently focused on obtaining new molecular magnets based on radical BEDT-TTF or TTF derivatives. In these series, the aim is to combine the magnetic and conducting properties in the same material via the radical donor. We report here the structural and the physical properties of three salts with donors TTF (ferrimagnetic insulator), TMTTF (antiferromagnetic insulator) and TMTSF (paramagnetic semiconductor), containing the Reinekes anion derivative [Cr(NCS)4(phenanthroline)]. The role of the crystal packing in determining the physical properties is discussed.
    L Li, JM Becker, LE Allan, GJ Clarkson, SS Turner, P Scott (2011)Structural and electronic modulation of magnetic properties in a family of chiral iron coordination polymers., In: Inorg Chem50(13)pp. 5925-5935
    The complexes FeL(2) [L = bidentate Schiff base ligands obtained from (R)-(+)-α-phenylethanamine and 4-substituted salicylaldehydes, substituent R = H, (t)Bu, NO(2), OMe, CN, OH] react with ditopic proligands 1,4-pyrazine (pz) or 4,4'-bipyridine (bpy), to give a family of optically pure Fe(II) polymeric chain complexes of formula {FeL(2)(μ-pz)}(∞) and {FeL(2)(μ-bpy)}(∞). Crystallographic studies show that a range of structures are formed including unidirectional and bidirectional linear polymers and canted zigzag chains. Interchain interactions via π-contacts and hydrogen bonding are also observed. SQuID magnetometry studies on all of the complexes reveal antiferromagnetic interactions, the magnitudes of which are rationalized on the basis of substituent electronic properties and bridging ligand identity. For complexes with bridging pz, the antiferromangnetic interaction is enhanced by electron-releasing substituents on the Fe units, and this is accompanied by a contraction in the intrachain distance. For complexes bridged with the longer bpy the intrachain antiferromagnetic couplings are much weaker as a result of the longer intrachain distance. The magnetic data for this series of chain complexes follow a Bonner-Fisher 1D chain model, alongside a zero field splitting (ZFS) model for Fe(II) (S = 2) as appropriate. The intrachain antiferromagnetic coupling J values, g-factors, and the axial ZFS parameter D were obtained.
    H Akutsu, S Ito, T Kadoya, J Yamada, S Nakatsuji, Scott Turner, Y Nakazawa (2018)A new Ni(dmit)2-based organic magnetic charge-transfer salt, (m-PO-CONH- N-methylpyridinium)[Ni(dmit)2]·CH3CN, In: Inorganica Chimica Acta482pp. 654-658 Elsevier
    A new Ni(dmit)2-based organic magnetic charge-transfer (CT) salt, (m-PO-CONH-N-methylpyridinium)[Ni(dmit)2]·CH3CN, where PO = 2,2,5,5-Tetramethyl-3-pyrrolin-1-oxyl free radical and dmit = 2-Thioxo-1,3-dithiole-4,5-dithiolate, was obtained, the crystal structure and magnetic properties of which are reported. Magnetic susceptibility of the CT salt obeys a combination of 1D ferromagnetic (1DF) Heisenberg (J1DF = +0.26 K) and Singlet-Triplet (ST) models (JST = -51.2 K) with mean field (MF) approximation (JMF = -6.7 K), suggesting that spins on the PO radicals form 1D ferromagnetic chains and spins on the Ni(dmit)2 monoanions forms spin dimers at low temperature, the latter of which was also confirmed by band calculations.
    M Mas-Torrent, J Vidal-Gancedo, X Ribas, J Veciana, C Rovira, SS Turner, P Day, K Wurst (2003)Bulk Spontaneous Magnetization in the New Radical Cation Salt TM-TTF[Cr(NCS)(isoquinoline)] (TM-TTF = Tetramethyltetrathiafulvalene), In: Inorganic Chemistry42(23)pp. 7544-7549
    A new organic-inorganic hybrid salt [TM-TTF][Cr(NCS) (isoquinoline)] (1) (TM-TTF = Tetramethyltetrathiafulvalene) has been synthesized. Compound 1 crystallizes in the triclinic P1 space group with a = 8.269(1), b = 10.211(2), and c = 11.176(2) Å, α = 89.244(9), β = 88.114(6), and γ = 74.277(7)°, V = 907.6(3) Å, and Z = 1. The crystal structure was resolved in the temperature range between 223 and 123 K, showing that changes in the crystal structure at low temperature result in stronger interactions between anions and cations. The packing of 1 consists of mixed anion-cation layers in the bc plane containing S···S and π-π anion-cation interactions, the layers being connected by very short S···S contacts between anions and cations. Magnetic measurements in a small external field show bulk spontaneous magnetization with a T of 6.6 K consistent with the presence of weakly coupled ferrimagnetic order in compound 1. The EPR measurements also demonstrate the interaction between the d and π electrons and the presence of an internal magnetic field brought about by the magnetic ordering.
    H Akutsu, R Hashimoto, J-I Yamada, S Nakatsuji, Y Nakazawa, SS Turner (2015)Structures and properties of new ferrocene-based paramagnetic anion octamethylferrocenedisulfonate and its ITF salt, In: INORGANIC CHEMISTRY COMMUNICATIONS61pp. 41-47 ELSEVIER SCIENCE BV
    N Kanbayashi, H Akutsu, J-I Yamada, S Nakatsuji, SS Turner (2012)A new ferrocene-containing charge-transfer salt, (TTF) [Fe(C H -CH(CH )NHCOCH SO ) ], In: Inorganic Chemistry Communications21pp. 122-124
    A novel ferrocene-containing dianion, Fe(C H - CH(CH )NHCOCH SO ) (1), has been prepared. The oxidation potential of the PPh salt is + 0.35 V (vs. SCE in PhCN), indicating that it is a stronger donor than TTF (tetrathiafulvalene) by + 0.03 V. The dianion provided a TTF salt, the structure and physical properties of which are reported. © 2012 Elsevier B.V. All rights reserved.
    H Akutsu, K Sato, S Yamashita, J-I Yamada, S Nakatsuji, SS Turner (2008)The first organic paramagnetic metal containing the aminoxyl radical, In: Journal of Materials Chemistry18(28)pp. 3313-3315
    We have prepared an organic magnetic anion, PROXYL-4-CONHCH SO (1). The electrocrystallisation of BEDT-TTF with PPh 1 gave the first purely organic paramagnetic metal, β″-(BEDT-TTF) (1). The salt shows a broad metal-insulator transition at approximately 210 K. © The Royal Society of Chemistry 2008.
    T Yamamoto, HM Yamamoto, R Kato, M Uruichi, K Yakushi, H Akutsu, A Sato-Akutsu, A Kawamoto, SS Turner, P Day (2008)Inhomogeneous site charges at the boundary between the insulating, superconducting, and metallic phases of beta '-type bis-ethylenedithio-tetrathiafulvalene molecular charge-transfer salts, In: PHYSICAL REVIEW B77(20)ARTN 2pp. ?-? AMER PHYSICAL SOC
    H Akutsu, S Yamashita, J-I Yamada, S Nakatsuji, SS Turner (2008)Novel purely organic conductor with an aminoxyl radical, α-(BEDT-TTF)(PO-CONHCHSO) ·2HO (PO = 2,2,5,5-tetramethyl-3-pyrrolin-1-oxyl free radical), In: Chemistry Letters37(8)pp. 882-883
    A novel bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF)-based salt with an aminoxyl radical 2,2,5,5-tetramethyl-3-pyrrolin-1-oxyl (PO) has been prepared. The salt has α-type 2-D conducting sheets and is a semiconductor with ρ = 26 Ω·cm and E = 0.31 eV. The temperature dependence of the magnetic susceptibility suggests that both the aminoxyl radical and the BEDT-TTF layer have local spin moments at room temperature. Copyright © 2008 The Chemical Society of Japan.
    This research focuses on the synthesis and characterisation of novel molecular salts with the potential to undergo spin crossover (SCO) transitions. SCO describes the reversible transition between the LS and HS states, which can occur in some first row transition metal complexes with d4 – d7 valence electrons, induced by changes in external stimuli such as temperature. The rearrangement of electrons during the SCO transition results in changes to the properties exhibited by the bulk material, which can be characterised by a number of methods. Such techniques used in this work include X-ray diffraction (XRD), SQUID (Superconducting Quantum Interference Device) magnetisation measurements, differential scanning calorimetry (DSC) and Mössbauer spectroscopy. Both cationic and anionic complexes of iron (II) and iron (III) have been synthesised with a range of ligands, based on 2,6-bis(pyrazol-1-yl)pyridines/pyrazines (dpp), salicylaldehyde triethylenetetramine (sal2-trien) and salicylaldehyde thiosemicarbazones (thsa). Ionic materials previously reported to exhibit molecular conductivity are used as counterions, such as tetrathiafulvalene (TTF+), 7,7,8,8-tetracyanoquinodeimethane (TCNQ-), nickel (II) complexes of maleonitriledithiolate ([Ni(mnt)2]-) and 2-thioxo-1,3-dithiole-4,5-dithiolato ([Ni(dmit)2]-). Metathesis reactions or electrocrystallisation experiments have been utilised, resulting in salts in one of the following combinations; [SCO]+[Conductor]- or [Conductor]+[SCO]- where SCO is a potential SCO metal complex and conductor is an ion which may support electrical conductivity. Whilst there are a limited number of examples of the former, no examples have been found of the latter combination. The synthesis of SCO double salts has also been attempted to give [SCO][SCO] compounds, by reacting cationic iron (II) complexes with dpp ligands with anionic iron (III) complexes with thsa ligands. All products have been analysed by a range of techniques, including elemental analysis, infra-red spectroscopy, XRD, DSC, SQUID magnetisation measurements, Mössbauer spectroscopy and variable temperature resistance measurements. A number of novel products have been synthesised and characterised, some of which exhibit interesting behaviours ranging from SCO transitions to semiconductivity to long range magnetic order. Iron (II) complexes with dpp-type ligands exhibited a range of SCO behaviours (hysteretic, abrupt, gradual) depending on the anion. A combination of iron (III) complexes with sal2-trien derivative ligands yielded both ferro- and ferrimagnetic compounds. It was determined that minor structural changes via halogen substitutions (Cl or Br) can change the nature of magnetic ordering. The presence of both iron (II) and iron (III) centres in the SCO double salts resulted in multiple SCO transitions.
    Enantioselective heterogeneous catalysis is an important and rapidly expanding research area. The two most heavily researched examples of this type of catalysis are the enantioselective hydrogenation of α-keto-esters over Pt-based catalysts and the enantioselective hydrogenation of β-keto-esters over Ni-based catalysts. These enantioselective surface reactions are controlled by the presence of adsorbed chiral molecules i.e. tartaric acid on the surface of the metal component of the catalyst. The work presented in this thesis focuses on two parts, the synthesis of pure nickel nanoparticles and enantioselective behavior of the modified nickel nanoparticles. The works on the synthesis of pure nickel nanoparticles were carried out using two methods, the reverse microemulsion and the reduction method. It was discovered that the reverse microemulsion method produced nickel oxide nanoparticles, whereas the reduction method produced pure nickel nanoparticles. Chiral modifications of Raney nickel (RNi) and C-supported catalysts were studied. The catalysts were employed in enantioselective hydrogenation of methyl acetoacetate (MAA) to (R) - and (S)-enantiomers of methyl 3-hydroxybutyrate (MHB). The effects of modification and hydrogenation parameters such as concentration of modifier temperature, pressure and solvent on the enantioselectivity of MAA hydrogenation were discussed. For RNi methanol was found to be the best solvent, with tartaric acid concentration 0.2 mol/L for achieving the highest enantiomeric excess under 8 bar at 70 oC. Characteristic features of the in-situ modification of Raney nickel and C-supported Ni were also evaluated and the results obtained were compared with the conventional (pre-modification) approach. Parameters for the conventional and in-situ methods were optimised in a series of experiments for both types of catalysts. The in-situ modified catalyst was found more active for both RNi and C-supported catalysts with 98 % and 42% enantiomeric excess, respectively.