THE VIBRATIONAL SPECTRA AND HARMONIC AS INITIO FORCE FIELDS FOR BICYCLO[2.2.1]HEPTANE AND SEVERAL ANALOGS

Abstract

Address: Department of Chemistry, University of Calgary, Calgary, Alberta, T2N IN4 Canada.Author Institution:The vibrational spectra in the region of 4000-100 $cm^{-1}$ are reported for 7-oxa- and 7-thiabicyclo[2.2.1]heptane and bicyclo[2.2.1]hept-2-ene. The spectra of bicyclo[2.2.1]heptane and 2,5-diene are included for comparison. The ab initio force fields are calculated at the STO-3G and 3-21G levels for each molecule. The force constants are scaled to fit the observed spectra. The transferability of the scaling factors within this series of compounds is examined for the two basis sets. The optimized force fields are compared with respect to eigenvectors and calculated frequencies