Multiconfiguration Self-Consistent-Field Calculations for Several States of Boron

Abstract

Multiconfiguration self-consistent-field calculations were performed on the following states of boron: 2s 2p, P, 2s2p, P, D, P, 2s 3s, 8, and 2p, 4S. For each state, onlyconfigurations resulting from the replacement of the valence-shell orbitals were used, and consequently only the valence-shell correlation was calculated adequately. The correlation orbital set consisted of one orbital in each of the symmetries s, p, and p (except for the 2s 3s, S state, where there were two orbitals of p symmetry). For the ground state, the value of 0.067 hartree was obtained for the valence-shell correlation energy. From the wave functions obtained, the term energies and the oscillator strengths for the allowed transitions were calculated and found to be in general agreement with the results of more elaborate calculations and experiments.

Lifetimes and transition probabilities of the boron atom calculated with the active-space multiconfiguration Hartree-Fock method

“…1.917 [2] 3.742 [2] 2.144 [5] 2.231 [5] ls 2s 4p P 2.066 [5] 2.135 [5] 2.651 [6] 2.666 [6] 3.722 [6] 3.740 [6] 1.197 [6] 1.198 [6] 7.728 [1] 6.165 [2] 1.708 [6] 1.718 [6] 2.444 [6] 2.458 [6] 8.757 [4] 9.17S [4] ls 2s 5p P 1.598 [2] S.675 [2] 1.574 [5] 1.596 [5] 7.164 [5] 7.176 [5] 1.112 [6] 1.107 [6] 1.501 [4] 1.8S3 [4] [5] 3.346 [5] 3.365 [5] ls 2s 4f F 2.624 [6] 2.6O2 [6] 1.232 [7] 1.234 [7] Ref. [12] Ref. [12] Ref.…”

<title>Theoretical study of ionization processes in BF<formula><inf><roman>3</roman></inf></formula> plasma</title>

“…For example, the lowest doublet AIS 2s2p 2 2 P is characterized by the experimental lifetime within 0.45 -0.54 ns (beam-foil spectroscopy, [11,12,16,17]). On the other side, the theoretical radiative lifetime lays within 0.46 -0.49 ns [14,15,18,19]. Again, comparing these values, we may conclude that the contribution of autoionizing mechanism to the 2s2p 2 2 P decay is negligible.…”

Autoionizing states of atomic boron

“…In the case of a neutral boron atom, however, the photoionization cross sections record is still rather scant. Various studies examined in detail the ground-state energy, the discrete spectrum [42][43][44][45][46][47][48][49][50][51][52][53][54][55][56][57][58][59], the electron affinity [60,61], the electron impact excitation and ionization [62][63][64][65][66], and the 1s core excitation [67] and core photoionization [68,69] of the boron atom. Discrete and photoionization spectra of the B + parent ion have also been computed [70][71][72][73][74][75].…”