Potential Energy Curves And Spectroscopic Properties Of The Low-lying States Of CaH、CsC And MgH Molecules

The potential energy curves(PECs)and electrical dipole moment(EDMs)of the low-lying states of CaH、CsC and MgH have been calculated using the internally contracted multi-reference configuration interaction plus Davidson modification(icMRCI+Q)approach with core-valence correlation and scalar relativistic corrections were taken into account.The spectroscopic constants and molecular constants of the A-S bound in more consistent with the experimental data have been obtained with the aid of LEVEL8.0 program fitting to the relevant potential energy curves.The results computed in this paper is good agreement with the available experimental data found.The results computed in this paper have certain reference value for further experimental and theoretical research of CaH、CsC and MgH moleculesThe 10 low-lying states of CaH molecule have been calculated,which avoided crossing in the B/B’~2Σ~+ and D~2Σ~+ state as well as other low-lying states was taken into account to explain a long-standing discrepancy exists between the experimental and theoretical analysis.The high-accuracy calculation have expanded the higher excited statesThe 13 low-lying states of CsC molecule first have been calculated with scalar relativistic corrections were implicit treated by ECP.The results computed in this paper is credible by RKR inversion for ground state X~4Σ~-.The 13 low-lying states of MgH molecule have been calculated with core-valence correlation and scalar relativistic corrections were taken into account.The potential energy curves of 3~2Σ~+、4~2Σ~+ and 5~2Σ~+ states is wave structure as a result of the avoided crossing interaction between ~2Σ~+ states The Rydberg states of MgH molecule is not well describe,the calculation in this paper involve the higher excited state 1~2Δ、2~2Δ and 3~2Π.