Ab initio MRD CI calculations on the cesium hydride (CsH) molecule

Ab initio multi-reference configuration interaction (MRD CI) calculations were carried out for the potential energy curves of the first 17 electronic states of the CsH molecule up to large bond distances (20 bohr). The 1Σ+ states were also calculated by means of relativistic all-electron SCF and CI using the spin-free no-pair operator with external field projectors. For the low-lying states, the spectroscopic parameters were determined. Dipole moments as well as the transition dipole moments: μ(X1Σ+→A1Σ+), μ(X1Σ+→B1Σ+), μ(A1Σ+→B1Σ+), were also calculated. Non-relativistic and relativistic results are compared. An analysis of the interactions in the 1,3Σ+ states is also proposed. (orig.)