Effect of spin-orbit interaction in photoionization of bromine

Abstract

The partial and total photoionization cross sections from the initial 2 P 3/2 ground state of atomic Br to the final Br ϩ 3 P J components across the 4p 4 (1 D 2)6d,8s(2 P, 2 D, 2 F, 2 S) autoionization resonances are presented. The multiconfiguration Hartree-Fock ͑MCHF͒ method has been used to calculate both bound and continuum wave functions in the nonrelativistic limit. The Breit-Pauli approximation is applied to determine the effect of spin-orbit interactions in the photoionization of atomic Br with the MCHF wave function as input. Our calculated results are compared with experimental data.

MCHF studies of partial photoionization cross section of atomic fluorine

“…The results were in excellent agreement with the experiment [8]. Earlier we also investigated the autoionization resonances observed experimentally in both the partial and total photoionization cross sections of atomic bromine between the 4p 4 ( 3 P-1 D) and 4p 4 ( 1 D-1 S) ionization thresholds using the MCHF + BP (Breit-Pauli) methods [9]. The effect of the spin-orbit interaction was considered through the Breit-Pauli approximation.…”

“…To study the effects of electron correlation accurately in both the initial and the final states, the MCHF method is used to perform the calculation [7,9,10]. Briefly a set of bound radial functions was determined with the traditional MCHF method, which describes the initial state and the final ionic states.…”

“…The effect of the spin-orbit interaction was considered through the Breit-Pauli approximation. In this paper, we applied the same MCHF method [7,9,10], for bound and continuum wavefunctions to accurately analyse the high resolution experimental data of the autoionization resonance series converging to the 2s 2 2p 4 1 S limit of F + in the partial as well as in the total photoionization cross sections for photon energies between the 1 D and 1 S thresholds. Our main emphasis was to take into account in detail the effects of electron correlation to accurately determine the energies of the resonance series including the 2s2p 6 ( 2 S) resonance, which interacts very strongly with the members of the 2p 4 ( 1 S)ns 2 S series.…”

“…Our main emphasis was to take into account in detail the effects of electron correlation to accurately determine the energies of the resonance series including the 2s2p 6 ( 2 S) resonance, which interacts very strongly with the members of the 2p 4 ( 1 S)ns 2 S series. Our previous study [7,9,10] indicated that the MCHF method is capable of taking into account the electron correlation and polarization effects very effectively in an ab initio manner essential for accurate identification of the structures appearing near the thresholds. In this study, the calculation is performed in LS coupling assuming that the spin-orbit and other relativistic contributions are not considerable.…”