The vibrational spectra and structure of indium(III) chloride, bromide, and iodide

Abstract

The far-infrared and Raman spectra of the crystalline indium trihalides have been recorded. The spectra of the trichloride and tri-iodide are completely compatible with their published crystal structures. The close similarity of the vibrational spectrum of the tribromide to that of the trichloride, rather than the tri-iodide, suggests that the tribromide exists as a polymeric layer lattice like indium and aluminium trichlorides. A simple numerical relationship between the frequencies of corresponding vibrations of In₂I₆ and Ga₂Br₆ has been observed.