Infrared Spectra and Geometry of Matrix-Isolated Diboron Tetrachloride and Tetrafluoride; Raman Spectra of the Liquids

Abstract

The infrared spectra of diborontetrachloride and diboron tetrafluoride molecules, isolated in a matrix of solid argon at liquid-hydrogen temperatures, along with the Raman spectra of the two compounds in the liquid phase are presented. Also reported are the 11B–10B isotopic shifts of the fundamental vibrations which have been used to establish the Vd molecular symmetry in the solid argon matrix. The Raman data also support a staggered configuration for B2Cl4 and B2F4 in the liquid phase. These data combined with the matrix infrared results are used to obtain a force constant analysis of both molecules using a Urey–Bradley force field.