Accurate potential energy functions and non-adiabatic couplings in the Mg plus H system

Marie Guitou (1) , A. Spielfiedel (2) , N. Feautrier (2)

1 MSME - Laboratoire de Modélisation et Simulation Multi Echelle
2 LERMA - Laboratoire d'Etude du Rayonnement et de la Matière en Astrophysique

Potential energy functions of the MgH molecule are investigated by the MRCI method using large active space and basis sets. The calculations are performed up to the Mg(3s3d, 1D) + H dissociation limit. The molecular constants compare well with the available data. The dipole moment functions exhibit a series of crossings due to the strong interactions between the states. Radial and rotational couplings among these states are also calculated, with a state-averaged MCSCF approach. This work will enable calculations of collisional cross sections and rate coefficients, important for the modelling of stellar spectra when collisions compete with radiative processes in non-LTE conditions. (C) 2010 Elsevier B. V. All rights reserved.

Domaines: Physique [physics]

Marie Guitou, A. Spielfiedel, N. Feautrier. Accurate potential energy functions and non-adiabatic couplings in the Mg plus H system. Chemical Physics Letters, 2010, 488 (4-6), pp.145--152. ⟨10.1016/j.cplett.2010.02.031⟩. ⟨hal-00692872⟩