A theoretical study on the electronically excited-state spectroscopic properties of phosphorus nitride

ABSTRACT

The potential energy curves of 103 Ω states generated from the 39 Λ–S states of PN have been calculated using the internally contracted multireference configuration interaction method with the Davidson modification. Core-valence correlation and scalar relativistic corrections, as well as the basis-set extrapolation to the complete basis set limit are considered. The spin–orbit coupling is computed using the state interaction approach with the Breit-Pauli Hamiltonian. The spectroscopic parameters and molecular constants of bound and quasibound Λ–S and Ω states are evaluated. Our calculated spectroscopic results agree quite well with the available experimental data. The interactions among different electronic states in curve crossing regions have been discussed with the help of computed spin–orbit coupling matrix elements. The perturbations and predissociation phenomena of the A¹$\mathrm{\Pi }$, b³$\mathrm{\Pi }$, D¹Δ, E¹Σ⁺, and 2¹$\mathrm{\Pi }$ states and so on have been revealed.

GRAPHICAL ABSTRACT

KEYWORDS:

• Potential energy curve
• spectroscopic parameter
• coupling
• perturbation
• predissociation

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

This work is sponsored by the National Natural Science Foundation of China under grant number 11274097, the Program for Science and Technology Department Henan Province in China under grant number 142300410201, and the Key Research Project of Xinyang Normal University in China under grant number 2021-ZDYY-LK-028.