SYNTHESIS AND STRUCTURE OF TLCUTITE3

The new compound TlCuTiTe3 has been synthesized from Tl5Te3 and the co rresponding elements and characterized by single-crystal X-ray diffrac tion methods. TlCuTiTe3 crystallizes in the space group C-2h(2)-P2(1)/ m of the monoclinic system with two formula units in a cell of dimensi ons a = 8.409(8) Angstrom, b = 3.956(3) Angstrom, c = 10.261(8) Angstr om, beta = 111.56(4)degrees, V = 317.5(4) Angstrom(3) (T = 115 K). The two-dimensional structure comprises slabs of alternating pairs of Ti octahedra and Cu tetrahedra. The slabs are separated by Tl+ cations co ordinated to Te2- anions in a monocapped trigonal prismatic fashion. W hereas the structure of the individual slabs in TlCuTiTe3 is strikingl y similar to those found in the related materials NaCuTiS3, NaCuZrSe3, and NaCuZrTe3, the packing of the slabs is different. Two-probe resis tivity measurements indicate that TlCuTiTe3 is a semiconductor.