Quantum Calculations of Intramolecular IR Spectra of Ice Models Using Ab Initio Potential and Dipole Moment Surfaces.
We report the IR spectra of two forms of ice in the monomer bend and OH-stretching regions, using recently developed ab initio potential and dipole moment surfaces for arbitrarily many water monomers. Coupling and anharmonicity of the intramolecular vibrational modes are taken into account using coupled three-mode variational calculations, within the local-monomer model. Spectra for the surface and core regions of these ice models are presented. The calculated spectra for the core region, with no adjustments, are in good agreement with experiment for the intramolecular OH-stretch and bend regions. Our analysis also shows a significant contribution from the overtone of the monomer bend to the OH-stretch region of the spectra.
Cherry L. Emerson Center for Scientific Computation and Department of Chemistry, Emory University, Atlanta, Georgia 30322, United States.
Hanchao
H
Liu
Cherry L. Emerson Center for Scientific Computation and Department of Chemistry, Emory University, Atlanta, Georgia 30322, United States.
Yimin
Y
Wang
Cherry L. Emerson Center for Scientific Computation and Department of Chemistry, Emory University, Atlanta, Georgia 30322, United States.
Joel M
JM
Bowman
IR spectra; ab initio water potential; ice models; intramolecular vibrational modes; local-monomer model; overtone of bend