Secondary bonding. Part 7. Crystal and molecular structures of diphenyltellurium dichloride and phenyltellurium trichloride

Abstract

The crystal and molecular structures of the title compounds have been determined from diffractometer data by the heavy-atom method. The crystals of diphenyltellurium dichloride (1) are orthorhombic, space group Pbca, with unit-cell dimensions (173 K)a= 7.644(2), b= 18.160(3), c= 18.014(3)Å, Z= 8, from 1 552 observed reflections [I/σ(I) 3.0], R= 0.036. Crystals of phenyltellurium trichloride (2) are triclinic, space group P, with unit-cell dimensions (290 K)a= 7.468(1), b= 8.610(1), c= 13.987(2)Å, α= 98.89(1), β= 92.10(1), γ= 90.81 (1)°, Z= 4, from 2 903 observed reflections, R= 0.018. The primary geometry about Te in (1) is based on a trigonal bipyramid with a vacant equatorial position, whereas (2) exhibits square-based pyramidal geometry for its two independent Te atoms; these are bridged by Cl atoms, to give a chain structure. Both structures exhibit longer Te ⋯ Cl interactions, though these are weak and perhaps of little significance in (2).