Calculation of the Raman Q branch of hydrogen in water and comparison with experiments

Document Type

Article

Publication Date

11-9-2018

Department

Department of Physics

Abstract

Calculations of the Raman Q-branch line shifts and line widths of H2 in water at three different pressures and at 280 K are presented and compared with available experimental results. The calculations are based on a perturbative method in which the perturbation consists of those components of the H2–H2O interaction that depend on vibrational and/or rotational coordinates. In the unperturbed system the rotovibrational motion of the hydrogen molecule is separated from the dynamics of the rest of the system. The unperturbed rotovibrational motion of H2 is treated quantum mechanically whereas the dynamics of the rest of the system is calculated by classical molecular dynamics (MD). The MD calculations are repeated with two different models for the water–hydrogen potential energy. Both are Lennard-Jones models but in one the parameters are derived from the Lorentz–Bertholet combination rules and in the other they are taken from gas phase scattering data. The numerical results for the Raman Q-branch spectra are compared with the measurements in order to determine which model is more dependable.

Publisher's Statement

Publisher's version of record: https://doi.org/10.1088/1361-6455/aaeae3

Publication Title

Journal of Physics B: Atomic, Molecular and Optical Physics

Share

COinS