Calculated spectroscopic properties of HgH2

Abstract

Ab initio calculations of the coupled cluster and spin-orbit configuration type, in conjunction with a small-core pseudopotential for the mercury atom, have been employed to construct near-equilibrium potential energy and electric dipole moment functions for HgH2. On that basis, rovibrational term energies and wavefunctions as well as transition dipole moments, absolute IR intensities and Einstein coefficients of spontaneous emission have been calculated variationally. Throughout, excellent agreement is obtained with recent experimental data from Fourier transform infrared emission spectroscopy. The gas-phase wavenumbers of the symmetric stretching and the bending vibrations of (HgH2)-Hg-202 and (HgD2)-Hg-202 ( in parentheses) are predicted to be 2012.3 (1442.8) cm(-1) and 784.3 (564.1) cm(-1), respectively. Various predictions are made for (HgHD)-Hg-202, for which no high-resolution spectra have yet been published.