Physical Properties of Some ET-Based Organic Metals and Superconductors with Mercury Containing Anions

Because of mercury atoms capability of forming the compounds with various coordination, the application of the electrolytes with Hg containing anions in electrochemical oxidation of ET (bis(ethylenedithio)tetrathiafulvalene) results in the formation of ET salts with the anions of different composition. The properties of organic metals and superconductors are briefly described for three families: 1) ET$_4$Hg$_{3-\delta}$X$_8$ (($\delta 0$, and a series of other peculiarities. Shubnikov-de Haas oscillations were observed for some salts of (ET)$_8$[ Hg$_4$X$_{12}$(C$_6$H$_5$Y)$_2$] family. The possible types of Fermi surface are discussed for these salts

Shubnikov-de Haas Oscillations in New Organic Conductors (ET)8\mathsf{_8}[ Hg4\mathsf{_4}Cl12\mathsf{_{12}}(C6\mathsf{_6}H5\mathsf{_5}Cl)2\mathsf{_2}] and (ET)8\mathsf{_8}[ Hg4\mathsf{_4}Cl12\mathsf{_{12}}(C6\mathsf{_6}H5\mathsf{_5}Br)2\mathsf{_2}]

The results of the investigations of Shubnikov-de Haas oscillations in the quasi-two-dimensional organic complexes (ET)${_8}$[ Hg$_4$Cl$_{12}$(C$_6$H$_5$Cl)$_2$] , where X = CI, Br in the magnetic fields up to 40 T were reported. These results allow one to obtain some information about Fermi surface in the mentioned complexes. Shubnikov-de Haas oscillations in the compound with X = Cl correspond at least to two different cylindrical sheets of Fermi surface with the cross-section in (bc)-plane of 13% and 20% Brillouin zone cross-section. Shubnikov-de Haas oscillations in the complex with X = Br correspond to one cylindrical sheet with the cross-section in (bc)-plane of 13% of Brillouin zone cross-section. The experimental results for the complex with X = Br more agree with the theoretical calculations of Fermi surface than for the complex with X = Cl.

On physical properties of the organic metal (BEDT-TTF)4Hg 3 _ δCl8

Conduction electron spin résonance study is presented together with static susceptibility, thermopower and IR absorption measurements for (BEDT-TTF) 4Hg3-δCl8. It is shown that the strong exchange interactions lead to a single ESR line broadened by the spin-orbit coupling ; the role of two-dimensionality of the salt is emphasized. The two-dimensionality of the spin ordering is also stated. The anomalies of the ESR parameters near 80 K may be associated with a phase transition caused probably by the deformation of the incommensurate Hg sublattice. Our study confirms that the anisotropy of the spectral (IR, ESR) properties does not necessarily agree with that of the transport properties of the organic metal.Nous présentons des études de résonance paramagnétique sur les électrons de conduction du (BEDT-TfF)4Hg3-δCl8, complétées par des mesures de susceptibilité paramagnétique statique, de force thermoélectrique et d'absorption IR. Nous avons montré que les interactions d'échange fortes conduisent à un spectre RPE simple, élargi par le couplage spin-orbite. La bidimensionalité du système de spin a été également confirmée. Des anomalies ont été observées près de 80 K pour certaines propriétés physiques ; nous supposons qu'elles sont provoquées par une déformation du réseau des ions Hg. Nous avons démontré que l'anisotropie spectrale (RPE, IR) n'est pas toujours comparable à l'anisotropie de transport électrique du métal organique

Quantum and semiclassical oscillations in the organic metal, (BEDO-TTF)(2)Cl-x(H2O)(y)

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New ambient pressure organic superconductor with T-c=8.1 K based on unsymmetrical donor molecule, ethylenedithiotetrathiafulvalene: (EDT-TTF)(4)Hg3-delta I8, delta similar to 0.1-0.2

Contains fulltext : 58779.pdf (publisher's version ) (Closed access)The new ambient pressure organic superconductor based on unsymmetrical donor, ethylenedithiotetrathiafulvalene, and the iodomercurate anion. (EDT-TTF)(4)Hg3-deltaI8, delta similar to 0.1-0.2, with T-c = 8.1 K has been synthesized. Transport and magnetic properties have been investigated. Upper critical fields have been studied under parallel and perpendicular magnetic fields up to 17 T in the temperature region down to 1.3 K. The data show that upper critical fields are within the paramagnetic limit in all directions. The coherence lengths indicate that (EDT-TTT)(4)Hg3-deltaI8, delta similar to 0.1-0.2, is a quasi-two-dimensional organic superconductor. (C) 2003 Elsevier B.V. All rights reserved

New ambient pressure organic superconductor with Tc = 8.1 K: (EDT-TTF)4Hg3-3II

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New BETS based molecular conductors with bromomercurate anions

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Characterization of the Fermi surface of (BEDO-TTF)(5)- CsHg(SCN)(4) (2) by magnetoresistance measurements and tight-binding band structure calculations

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