Chemical Physics Letters, Vol.668, 23-28, 2017
Collisional rate coefficients of SiH(X-2 Pi) open-shell molecule induced by its collision with He(S-1)
New adiabatic potential energy surfaces (PESs) for (2)A' and (2)A '' states of SiH((XP)-P-2)-He(S-1) complex have been calculated at the restricted coupled cluster level of theory including single, double and triple excitation [RCCSD(T)]. The RKHS method was used for the analytic fit of these PESs. The resulting PESs were employed later in the close-coupling approach for the computation of the inelastic integral cross sections which take into account the fine-structure of the SiH radical. Scattering calculations, are done on a grid of collision energies large enough to ensure converged state-to-state rate coefficients for the temperature ranging from 8 K up to 300 K. (C) 2016 Elsevier B.V. All rights reserved.
Keywords:Open-shell;Potential energy surface;Inelastic rotational collision;Cross sections;Close-coupling;Rccsd(t)