A fourth polymorph in the family of BEDT‐TTF salts with thiocyanatocuprate(I) anions: (BEDT‐TTF)4Cu3(NCS)5

A new crystallographic modification was found in the family of BEDT-TTF salts containing thiocyanatocuprate(I) anions. The cation radical salt crystallizes in the P1{(bar)} space group with a=8.2720(9)angstrom, b=19.099(2)angstrom, c=43.758(5)angstrom, alpha=81.088(4)degrees, beta=87.253(4)degrees, gamma=83.790(4)degrees, V=6786.2(13)angstrom 3 at 150K. The BEDT-TTF radical cations pack in an a-type motif, but every four columns, there is a slip in the layer. Where this slip occurs, the stacks are coupled in a beta manner. The material exhibits semiconductive behavior with an activation energy of 0.13eV above 250K and 0.22eV below. Packing motif of the (BEDT-TTF)4Cu3(NCS)5 structure.