Infrared spectrum of HXeI revisited: anharmonic vibrational calculations and matrix isolation experiments

Anharmonic correlation-corrected vibrational self-consistent-field (CC–VSCF) calculations are reported for the neutral HXeI molecule. Fundamental, overtone and combination frequencies and their absorption intensities are computed, and compared with previous and new experimental data from FTIR matrix isolation measurements. Agreement between experiment and calculations extend the identification of the HXeI molecule, and the calculations prove useful in aiding assignment of new observed transitions. The results show that especially the Xe–H bond of HXeI is highly anharmonic. While the agreement between theory and experiment is useful for assignment, quantitative discrepancies still remain due to the deficiency of MP2 theory to describe the highly anharmonic surface.