Synthesis, crystal structure and electrical properties of [Pd(dmit)2]2− and [Pd(dmit)2]0.5− anion complexes with 2-dimethylamino-1,3-dithiolanylium as counter cation

The synthesis, structural characterization and electrical conductivity measurement of [MDA]2[Pd(dmit)2] (1 and [MDA] [Pd(dmit)2]2 (2) (MDA = 2-dimethylamino-1,3-dithiolanylium, dmit = 1,3-dithiole-2-thione-4,5-dithiolate) are reported. Complex 1 consists of two Pd(dmit)2 anions and four MDA cations in the unit cell and the anions are separated by cations in the crystal; the conductivity is about 10−7 S cm−1. The structure of complex 2 is made of stacked Pd(dmit)2 dimers. The modes of intra- and inter-dimer molecular overlapping are both of slide-away types. Pd atoms deviate from planes formed by four ligand S atoms 0.07 Å apart to approach each other. Room-temperature conductivity is 10–70 S cm−1. Temperature-dependent conductivity measurement of this compound indicated that it is a semiconductor with a low activation energy (0.043 eV).