Rare-earth elements in molecular conductors: Crystal and electronic structures

The new molecular conductors with some rare-earth metal-complex anions (ET)5[M(NCS)6NO3]·C2H5OH (M=Dy (1), Y (2), Ho (3)) and (TMTSF)3[Y(NO3)5]·2C6H5Cl (4) as well as a new low-temperature modification of tetra-n-buthylammonium dysprosium(III) complex, (Bu4N)3[Dy(NCS)4(NO3)2] (5) used for the preparation of salt 1 were synthesized and studied by X-ray crystallography at 295 and 110 K. Salts 1-3 have a layered crystal structure with a new packing type of the radical cation layers, called an ω-type. Electronic structure calculations for the compounds 1-3 showed that the paired ET molecules have a positive charge +1 and the single ET molecules are neutral. The directions of the TMTSF stacks in the neighboring organic layers of 4 are practically perpendicular so that salt 4 can be regarded as a precursor of 2D conductors formed by mutually perpendicular directions of conductivity