Crystal structure, electrical transport, electronic band structure and quantum oscillations studies of the organic conducting salt θ-(BETS)4HgBr4(C6H5Cl)

Abstract The θ-(BETS) 4 HgBr 4 (C 6 H 5 Cl) radical cation salt was prepared by electrochemical crystallization. Its crystal structure was determined by single crystal X-ray diffraction. The electronic structure was studied by means of the extended Huckel tight-binding band approximation. Electrical resistance of θ-(BETS) 4 HgBr 4 (C 6 H 5 Cl) as a function of temperature shows a metallic behavior down to 1.4 K with a metal–semiconductor–metal transition within 240–246 K range. Shubnikov-de Haas oscillations showed a low-frequency spectrum with two frequencies F 1 =40 T and F 2 =210 T, which correspond to the proposed Fermi surface. The third frequency which has to be observed according to the calculations was not revealed in the experimental conditions.