The interpretation of the neutron inelastic scattering and infrared absorption spectra of chromous acid using the double Morse potential model

Abstract

The neutron inelastic scattering and infrared absorption spectra of chromous acid are analyzed using a double Morse potential model. The proton tunneling frequency is assigned to a peak at 548 cm−1 and the ‖0〉→‖2〉 transition to the band at 2050 cm−1 in the neutron inelastic scattering spectrum. These assignments differ from those (viz. ‖0〉→‖1〉=226 cm−1, ‖1〉→‖2〉=1650 cm−1) made prior to the availability of the neutron inelastic scattering data. The proton tunneling frequency is thus assigned to a peak of considerably higher frequency. The model calculations also explain the infrared absorption spectrum of deuterated chromous acid and resolve previous discrepancies in the crystallographic data for chromous acid.