The Br—O bond in halogen oxides — Empirical force constants and electronic characteristics

Abstract

A number of bromine oxides and mixed chlorine–bromine oxides for which spectroscopic information is available have been chosen to investigate the nature and characteristics of the Br—O bond. The study consists of the empirical determination of stretching force constants for these bonds from observed vibrational spectroscopic data and the analysis of the topological characteristics of the bonds via ab initio calculations. The latter have been performed at the MP2 level with a 6-311+G(2df) basis set, to provide a uniform and systematic framework for comparing these species. Three types of Br—O bonds have been found, with different characteristics of strength and electron density. The results are compared with those recently found for the Cl—O bond in chlorine oxides.Key words: bromine oxides, bond electronic structure.