Transition properties of X1 Σ+, A1Σ-, B1 Δ, C1 Π, a3 Σ+, b3 Δ, c3 Π, and d3 Σ- states of PO+

The potential energy curves of the X-1 Sigma(+), A(1) Sigma(-), B-1 Delta, C-1 Pi, a(3) Sigma(+), b(3) Delta, c(3) Pi, and d(3) Sigma(-) states of PO+ and the transition dipole moments between these states were calculated using the CASSCF method, and then the icMRCI approach. To accurately compute the transition properties, core-valence correlation and scalar relativistic corrections were taken into account. The spin-orbit coupling calculations were used to determine the transition properties of the A(1) Sigma(-), B-1 Delta, a(3) Sigma(+), and b(3) Delta states, from which no spontaneous emissions were generated owing to the limitations from the dipole-allowed transition selection rule. The radiative lifetime was approximately 10 - 100 ns for the C-1 Pi state and 10 mu s for the c(3) Pi state. Among these dipole-allowed transitions, the emissions from the C-1 Pi - X-1 Sigma(+) system was the strongest and was followed by the C-1 Pi - A(1)Sigma(-) and c(3) Pi - a(3) Sigma(+) transitions. The radiative lifetime was approximately 10 - 100, 10 - 100, and 100 mu s for the A(1) Sigma(-)(0), d(3) Sigma(-)(0+), and d(3) Sigma(-)(1) states, respectively. Those were of the order of 0.1 - 10, 10, 10 - 100, 1 - 100, and 0.1 - 1 ms for the B-1 Delta(2), a(3) Sigma+(1), a(3) Sigma(+)(0-), b(3)Delta(1), and b(3)Delta(2) states, respectively. Among the spontaneous emissions generated from these Omega states, those from the A(1)Sigma(-)(1) - a(3)Sigma+(0-), A(1)Sigma(-)(1) - a(3)Sigma(+)(1), B-1 Delta(2) - b(3)Delta(3), b(3)Delta(2) - a(3)Sigma+(1), d(3)Sigma(-)(0+) - a(3)Sigma(+)(0-), and d(3)Sigma(-)(1) - a(3)Sigma+(1) transitions were relatively strong. The transition properties reported herein are expected to provide useful guidelines for the detection in future experiments. (C) 2021 Elsevier Ltd. All rights reserved.

Automated summary

This study calculated the potential energy curves and transition dipole moments between different states of PO+ using various methods, taking into account core-valence correlation, scalar relativistic corrections, and spin-orbit coupling. The results showed variations in the radiative lifetimes and intensities of different transitions, providing useful guidelines for detection in future experiments.