Vibrational spectra of bicyclo[1. 1.0]butane

Abstract

1. The vibrational spectra of bicyclo[1.1.0]butane were investigated in three aggregated states, and assignments of the frequencies of the basic vibrations of this molecule were proposed. 2. The frequencies of the stretching vibrations of the methylene groups of bicyclobutane are substantially lowered in comparison with cyclopropane and other three-membered rings. This is evidence of a substantial difference of the electronic spectrum of the methylene group of bicyclobutane from other three-membered rings.