Abstract
Evidence concerning the occurrence of a first-order phase transition around 260 K in the organic metal κ-(BETS)2C(CN)3 is reported and the effect of the transition on the crystal and electronic structure of the salt is discussed. Determination of the crystal structure at 50 K has shown that the main structural change brought about by the transition affects the anion sublattice. Although there are noticeable changes in the chalcogen⋯