Electronic states and spectroscopic properties of MgH in absence and presence of spin–orbit coupling − a configuration interaction study

ABSTRACT

Electronic spectrum of astrophysically important molecule magnesium hydride (MgH) has been studied using configuration interaction methodology excluding and including spin–orbit coupling. Potential energy curves of several spin-independent (Λ−S) electronic states have been constructed and spectroscopic constants of low-lying bound Λ−S states within 8.2 eV of term energy are reported in the first stage of calculations. The X²Σ⁺ is identified as the ground state in the Λ−S level. In the subsequent stage, the spin–orbit interaction has been incorporated and its effects on the potential energy curves and spectroscopic features of different electronic states of the species have been investigated. The X²Σ⁺_1/2 is identified as the spin–orbit (Ω) ground state of the species. Transition moments of several dipole-allowed transitions are computed in both the stages and radiative lifetimes of the corresponding excited states are computed. Electric dipole moments (µ) for a number of low-lying bound Λ−S states as well as several low-lying Ω-states are also calculated in the present study.

KEYWORDS:

• Magnesium hydride
• configuration interaction
• spin–orbit coupling
• electronic states
• spectroscopic properties

Acknowledgments

The author thanks Prof. Dr R. J. Buenker, Wuppertal, Germany for his kind permission to use CI codes. The author is also grateful to Prof. K. K. Das, Jadavpur University, India for his kind cooperation and advice.

Disclosure statement

No potential conflict of interest was reported by the author.