Relativistic configuration interaction calculations of low-lying states of PbF

Abstract

Relativistic configuration interaction calculations are carried out on the low-lying states [1/2, 3/2, 1/2(II), 3/2(II), 4Σ−1/2, B2Σ+1/2 ] of PbF, together with comparison calculations on the five low-lying λ-s states (2Π, 2Σ+, 4Σ−, 2Δ, 4Π). Spectroscopic properties and dissociation energies of these states are computed and compared with the available experimental results. The ground state spin-orbit splitting is calculated to be 7895 cm−1. Our calculations enable the assignment of experimentally observed X1, X2, A, and B states to ‘u2Π1/2, 2Π3/2, 2Σ+1/2, and 2Σ+1/2(II), respectively. The B state is assigned to the lowest Rydberg state arising from σ2σ′R π4 configuration. Calculations of 4Σ−1/2 (in type C coupling) and 3/2(II) state are reported which are yet to be observed.