The crystal structure of tetraindium triselenide

Abstract

The crystal structure of tetraindium tritelluride (In4Te3) has been determined from X-ray photographic data taken with Mo Ka radiation and refined to a residual of 0.08. The phase, which is shown to be isomorphous with In4Se3, is orthorhombic, space group Pnnm, with a= 15.630, b= 12.756, e=4.441 ,~, Z = 4. The material is composed of two centrosymmetrically related interlocking continuous sheets of atoms running perpendicular to a. These are constructed of interlinked five-membered indium-tellurium rings forming chains parallel to e, the chains being cross-linked by strongly bound In-In-In units forming, in ionic terms, the homonuclear triatomic cation (In3) s+.