Fully complex implementation of the Robert–Bonamy formalism: Half widths and line shifts of H2O broadened by N2

Abstract

The complex semiclassical formalism of Robert and Bonamy is used to calculate both half widths and line shifts for water vapor in a bath of nitrogen. The assumed intermolecular potential is a combination of electrostatic, Lennard-Jones 6-12 atom–atom, induction, and dispersion terms. The complex valued resonance functions have been previously evaluated when the assumed potential was electrostatic only. In this work these functions are evaluated when the potential is extended to include the atom–atom terms. Calculations made in the 3ν1+ν3 vibrational band of H2O are in good agreement with experimental results for both the half width and line shifts. It is shown that the imaginary parts are important for both the line shift and half width calculations.