Theoretical investigation of the diatomic Van der Waals systems Ca+He and CaHe

An ab initio investigation has been performed for the ground and several excited states of CaHe and CaHe systems. The potential energy curves, spectroscopic constants, vibrational levels energies and electric dipole moments have been calculated and analyzed. The ab initio method uses the pseudo-potentials technique, Core Polarization Potentials (CPP) and Full Configuration Interaction (FCI). The number of active electrons of Ca+He and CaHe are reduced to one and two active electrons, respectively. The examination of these numerous results shows interesting structures and behaviors resulting from a collision induced process that involves calcium and helium atoms. An excellent agreement is found with the available results which confirms the reliability of our calculation. (C) 2017 Elsevier B.V. All rights reserved.