First molecular conductors with 8,8′-dibromo cobalt bis(dicarbollide) anion

New molecular conductors on the base of 8,8'-dibromo cobalt bis(dicarbollide) anion, (BEDT-TTF)(2)[8,8'-Br-2-3,3'-Co(1,2-C2B9H10)(2)] (1), (BEDT-TTF)[8,8'-Br-2-3,3'-Co(1,2-C2B9H10)(2)] (2) and (BMDT-TTF)(4)[8,8'-Br-2-3,3'-Co(1,2-C2B9H10)(2)] (3) were synthesized and their crystal structures and electrical conductivities were determined. All the radical cation salts prepared were found to be semiconductors. The introduction of two bromine atoms in the cobalt bis(dicarbollide) anion produces a strong effect on crystal structure and electrical conductivity of the prepared materials. (C) 2008 Elsevier Masson SAS. All rights reserved.