Hexaiododisilane

Abstract

The title compound, Si2I6, was prepared by reaction of silicon tetraiodide with finely divided metallic silver and subsequently purified by sublimation. The crystal structure can be regarded as an approximately dense packing of I atoms with the sequence ABAC with Si-Si dumb-bells occupying 1/6 of the octahedral sites. In an alternative description the structure is constituted of hexaiododisilane molecules with staggered conformation forming isolated slightly distorted octahedra with Si-Si dumb-bells in its centres.