The vibrational spectra of the carboranes. Part II. 4,5-Dicarba-nido hexaborane(8) and its C-methyl derivatives

Abstract

The Raman spectra of 4,5-C₂B₄H₈, C₂B₄H₇Me, and C₂B₄H₆Me₂ are presented, together with qualitative intensities and states of polarisation. Vibrational assignments are given for C₂B₄H₈ using both Raman and remeasured i.r data and the results of published i.r. deuteriation studies, and comparative assignments are given for the methylated derivatives. The vibrational frequencies are partially correlated with the bonding in the polyhedral framework, and compared with data for the small closo-carboranes.