Synthesis, Structure, Electrical Properties, and Band Structure Calculations of TiAsTe

The new compound TiAsTe has been synthesized by the reaction of the elements in a LiCI/KCI flux at 923 K. The compound crystallizes with four formula units in space group Immm of the orthorhombic system in a cell at 153 K of a = 3.5730(8) A, b = 5.249(1) A, c = 12.794(3) A, V = 240.0(1) A. The structure, which is of the NbPS structure type, is a three-dimensional extended framework built from bicapped TiAs4Te4 trigonal prisms. It may be considered to comprise [TiTe] slabs perpendicular to [001] that are interspersed with linear [As] chains running along [010]. The As-As distances alternate at 2.554(2) and 2.695(2) A. Electrical and thermopower measurements indicate that TiAsTe is an n-type metallic compound. Density functional theory calculations help rationalize the chemical bonding and physical properties.