MRCI study on potential energy curves and spectroscopic properties of HF molecule

•Accurate spectroscopic parameters of the bound states (X1Σ+,B1Σ+,11Δ,3ΠR1,3ΔR1,3ΔR1,3ΣR1-,3ΔR2) of HF molecular have been obtained.•The 3ΣR1- state is studied at the first time.•Einstein coefficients (Aυ′υ″)(Aυ′υ″), Franck–Condon factors (qυ′υ″)(qυ′υ″) for B1Σ+−X1Σ+ systems are predicted.•The transition dipole moments (TDM) and radiative lifetime (τυ′)(τυ′) for B1Σ+−X1Σ+ systems are evaluated.

The potential energy curves of the low-lying electronic states of Hydrogen fluoride (HF) have been investigated by using multireference configuration interaction (MRCI) approach in combination with cc-pV5Z basis sets for H and aug-cc-pV6Z basis sets for F. Three singlet states (X1Σ+, B1Σ+, 11Δ), two triplet valence states (3ΠV,3ΣV+) and five triplet Rydberg states (3ΣR1+,3ΠR1,3ΔR1,3ΣR1-,3ΠR2) of HF molecular are identified. 3ΠV   and 3ΣV+ states are repulsive, the spectroscopic parameters (De, Re, ωe, Be and Te  ) of the bound states are derived in the present work. We find that the order of energy levels of 3ΣR1+,3ΠR1,3ΔR1 electronic states is different with other literatures, 3ΣR1+ is the lowest in these three states, which undergoes a strongly avoided crossing with the valence state 3ΣV+. The 3ΣR1- state is studied at the first time. In addition, the dipole moments (DM), transition dipole moments (TDM), Einstein coefficients (Aυ′υ″)(Aυ′υ″), Franck–Condon factors (qυ′υ″)(qυ′υ″) and radiative lifetime (τυ′)(τυ′) for B1Σ+−X1Σ+ systems are predicted.

Graphical abstractThe PECs of the ground state and seven triplet states of HF molecule.Figure optionsDownload full-size imageDownload as PowerPoint slide