title: Ab initio calculations on potential energy curves and radiative lifetimes for the band systems A(2)Π-X(2)Σ(+) of magnesium monohalides MgX (X=F, Cl, Br, I).
abstract: Ab initio calculations on potential energy curves (PECs), spectroscopic constants, transition dipole moments, radiative transition probabilities and lifetimes for the ground state (X(2)Σ(+)) and the first excited state (A(2)Π) of MgX (X=F, Cl, Br, I) molecules are determined by high-level internally contracted multi-reference configuration interaction (ic-MRCI) method. In order to improve the calculation, the Davidson modification (+Q) and scalar relativistic correction are included. The present results show that most of spectroscopic constants are in accordance with the measurements, the equilibrium internuclear distance Re increases while the other spectroscopic constants reduce along with the increasing of the atomic number of the halogen from F to I. Diagonal vibrational transitions are found to be dominant for the A(2)Π→X(2)Σ(+) system of MgX molecules. The corresponding radiative lifetimes of ν'=0 are computed to be 7.24, 9.98, 18.94 and 22.72 ns for MgF, MgCl, MgBr, and MgI, respectively. The calculated result of MgF molecule is in good agreement with the recent theoretical result of 7.16 ns, with a small relative error percent of 1.11%.
authors.affiliation: College of Mathematics and Physics, Jinggangshan University, Ji'an 343009, China; Institute of Atomic and Molecular Physics, Jilin University, Changchun 130012, China.
authors.forename: Dong-lan
authors.initials: DL
authors.lastname: Wu
authors.affiliation: College of Mathematics and Physics, Jinggangshan University, Ji'an 343009, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Tan
authors.affiliation: College of Mathematics and Physics, Jinggangshan University, Ji'an 343009, China.
authors.forename: Jiu-ying
authors.initials: JY
authors.lastname: Qin
authors.affiliation: College of Mathematics and Physics, Jinggangshan University, Ji'an 343009, China.
authors.forename: Hui-jun
authors.initials: HJ
authors.lastname: Wan
authors.affiliation: College of Mathematics and Physics, Jinggangshan University, Ji'an 343009, China.
authors.forename: An-dong
authors.initials: AD
authors.lastname: Xie
authors.affiliation: Institute of Atomic and Molecular Physics, Jilin University, Changchun 130012, China; Jilin Provincial Key Laboratory of Applied Atomic and Molecular Spectroscopy, Jinlin University, Changchun 130012, China. Electronic address: yanbing@jlu.edu.cn.
authors.forename: Bing
authors.initials: B
authors.lastname: Yan
authors.affiliation: Institute of Atomic and Molecular Physics, Jilin University, Changchun 130012, China; Jilin Provincial Key Laboratory of Applied Atomic and Molecular Spectroscopy, Jinlin University, Changchun 130012, China. Electronic address: dajund@jlu.edu.cn.
authors.forename: Da-jun
authors.initials: DJ
authors.lastname: Ding
keywords: MRCI+Q; MgX; Radiative lifetimes; Spectroscopic constants; Transition dipole moments