Potential Energy Function for State X1∑+ of LaH

The present work has derived the potential energy function for the ground state X1∑+of LaH in Murrell-Sorbie function form. In the first place, the electronic state and it′ s rea sonable dissodation limits are correctly determined based on Atomic and Molecular Reaction Statics (AMRS), and then, using the relativistic compact effective potential (RCEP) for La, the equilibrium geometry and dissociation energy for LaH have been calculated by the QCISD method. The calculated results for Re'De' Be' αe' ωe and ωexe are 2.125A, 2.623eV,3.7333cm-1, 0.0723 cm-1, 1461.73cm-1 and 21.383cm-1 respectively, which are in good agreement with experimental or calculated values in references.