Calculation of the H218O rotational energy levels for the first hexad of interacting vibrational states

Abstract

The experimental rotational energy levels of six vibrational states, (021)-(101)-(120)-(200)-(002)-(040) (Canad. J. Phys., 64, 746–761 (1986)), of the H218O molecule have been fitted for determining the rotational, centrifugal, and resonance parameters. To correctly reproduce the initial experimental data, the effective vibration-rotation Hamiltonian has been improved. The parameters obtained from the fitting reproduce the initial experimental data with an average accuracy better than 0.01 cm−1.