Large-scale multiconfiguration Hartree-Fock and configuration-interaction calculations of isotope shifts and hyperfine structures in boron.

Abstract

A new isotope shift program, part of the multiconfiguration Hartree-Fock (MCHF) atomic structure package, has been written and tested. The program calculates the isotope shift of an atomic level from MCHF or configuration-interaction (CI) wave functions. The program is specially designed to be used with very large CI expansions, for which angular data cannot be stored on disk. To explore the capacity of the program, large-scale isotope shift calculations were performed for the 1${\mathit{s}}^{2}$2${\mathit{s}}^{2}$2p $^{2}$P, 1${\mathit{s}}^{2}$2${\mathit{s}}^{2}$3s $^{2}$S, and 1${\mathit{s}}^{2}$2s2${\mathit{p}}^{2}$ $^{2}$D levels in boron. From the isotope shifts of these levels the transition isotope shifts were calculated for the two resonance transitions. The calculated transition isotope shifts are in very good agreement with experimental shifts. As an additional test of the quality of the CI wave functions, the hyperfine structure was calculated for all levels.