Vibration Frequencies , Normal Coordinates and IR Absorption Intensities of 1-; 1,2-; 1,3- and 1,2,3- Methylene Cyclobutane Dirivatives

Abstract

SCF-MO calculations of the vibration frequencies and IR absorption
intensities, applying the MINDO/3-FORCES method, are reported for the four
molecules, mono-, di- (1,2- and 1,3-), and 1,2,3-trimethylene cyclobutane. In addition,
normal coordinate analysis of all vibration modes is described for each molecule. The
obtained results allow interesting correlations between the frequencies of similar
modes as calculated for the different methylene cyclobutanes.