Vibrational Spectra, Conformations, and Theoretical Calculations for Cyclohexane, Chlorocyclohexane, Bromocyclohexane and their Isotopomers

The infrared and Raman spectra of cyclohexane and its d$_{\mathrm{11}}$ and d$_{\mathrm{12}}$ isotopomers have been recorded and analyzed. The studies were complemented by \textit{ab initio} (MP2-ccpVTZ) and density functional theory (DFT/B3LYP-ccpVTZ) calculations. The conformational energies of different structures of the molecules were calculated. Vibrational spectra were also recorded for chlorocyclohexane-d$_{\mathrm{0}}$ and -d$_{\mathrm{11}}$ and bromocyclohexane-d$_{\mathrm{0}}$ and -d$_{\mathrm{11}}$. Theoretical computations were also performed to calculate the spectra and molecular conformational energies of the halocyclohexanes.