Structures and Properties of New Organic Molecule-Based Metals, (D)2BrC2H4SO3 [D = BEDT-TTF and BETS]

Abstract

An organic anion, 2-bromoethanesulfonate (BrC2H4SO3−), provides one bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) and two bis(ethylenedithio)tetraselenafulvalene (BETS) salts, the compositions of which are β’’-β’’-(BEDT-TTF)2BrC2H4SO3 (1), β’’-β’’-(BETS)2BrC2H4SO3 (2), and θ-(BETS)2BrC2H4SO3 (3), respectively. Compound 1 shows a metal–insulator transition at around 70 K. Compound 2 is isomorphous to 1, and 3 is polymorphic with 2. Compounds 2 and 3 show metallic behavior at least down to 4.2 K. The pressure dependence of the electrical resistivity of 1 is also reported.

Role of the Anion Layer’s Polarity in Organic Conductors β″-(BEDT-TTF)2XC2H4SO3 (X = Cl and Br)

“…The disparity may be caused by different rates of temperature change, 0.72 and 1.0 K min −1 for cooling and heating, respectively. On cooling, after the phase transition, the magnetic susceptibility decreases with decreasing temperature, which follows the same form as that of 2 19 from room temperature to the MI transition temperature (70 K). Below 70 K, the susceptibility of 2 decreases toward zero.…”

“…Accordingly, we have reported the BEDT-TTF, BEST, and BETS salts of the HOC 2 H 4 SO 3 − anion 18 and the BEDT-TTF and BETS salts of BrC 2 H 4 SO 3 − . 19 In this article, we report a new BEDT-TTF salt of ClC 2 H 4 SO 3 − and a new interpretation of the electronic structure of the previously reported BrC 2 H 4 SO 3 − salt of BEDT-TTF. 20 on olex2 21 gave the ratio of 1 and 2 of approximately 50:50.…”

“…1L is isomorphous with β″-β′′-(BEDT-TTF) 2 BrC 2 H 4 SO 3 (2) from room temperature to at least 100 K. The crystal structure and physical properties of 2 have already been reported. 19 2 does not have a first-order phase transition but shows a broad MI transition at 70 K. In ref 19, it was stated that 2 belongs to the type III category. However, in light of the discussion above, a more detailed analysis shows that the anion in 2 has a dipole moment of 9.9 debye 22 and is tilted by approximately 5.5°away from the conducting plane.…”

Perspectives on Molecular Materials—A Tribute to Professor Peter Day

“…The contribution by H. Akutsu et al at Osaka University (Japan) and S. S. Turner at the University of Surrey (UK), ref. [16], reports three novel radical salts prepared with the organic donors bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) and bis(ethylenedithio) tetraselenafulvalene (BETS) with the organic anion 2-bromoethanesulfonate (BrC 2 H 4 SO 3 − ). The salt with BEDT-TTF presents a double β" packing, whereas the two BETS salts present a double β" packing or a θ-type packing in the organic donors.…”

A 2D Interactive Spin Ladder System, δ′-(BEDT-TTF)2ClC2H4SO3·H2O

“…8 Accordingly, we have recently reported several charge-transfer (CT) salts of HOC 2 H 4 SO 3 −9 and BrC 2 H 4 SO 3 − . 10 In this communication, we report a BEDT-TTF-based purely organic semiconducting 2D interactive spin ladder system, δ′-(BEDT-TTF) 2 ClC 2 H 4 SO 3 •H 2 O (1). Typi-cally, spin ladders are isolated from each other by nonmagnetic species, 11 but here the spin ladders interact with each other, hence the term "interactive".…”