Charge transfer ionic character illustration for strontium hydride ion through a diabatic investigation

Adiabatic and diabatic studies are performed for the strontium hydride ion (SrH)⁺. Potential energy surface and electric dipole moment for the ground and all excited states dissociating up to the charge transfer ionic limit Sr²⁺H⁻ have been investigated and analyzed in adiabatic and diabatic representations. The adiabatic approach uses the pseudo potential for the strontium atom complemented by core polarization potential operators, reducing the calculation to a two effective electrons system where full configuration interaction can be easily performed. The adiabatic results have been improved by a simple correction of the hydrogen electron affinity for all ¹Σ⁺ states. The diabatic results reveal the strong imprint of the charge transfer ionic state in the ¹Σ⁺ adiabatic states.