Many-body theory of the nuclear quadrupole coupling in the boron atom

Abstract

The linked-cluster many-body perturbation theory is utilized to obtain an accurate value of the electric field gradient for the lowest ${}_{}{}^2{}_{}{}^{}P_{\frac{3}{2}}^{}{}_{}{}^{}$ state of atomic boron. This diagrammatic method permits us to examine the relative importance of angular-polarization and dynamic correlation effects on the electric field gradient. Also, a detailed comparison with another many-body theory of contributions classified by Hartree-Fock labels is made. The resulting quadrupole shielding factor $R=0.0989\mathrm{}\pm 0.0099$ yields a field gradient $q=0.279\mathrm{}57\pm 0.00276$ a.u. Finally, we obtain from the quadrupole coupling constants the nuclear quadrupole moments of ${}_{}{}^{10}{}_{}{}^{}\mathrm{B}$ and ${}_{}{}^{11}{}_{}{}^{}\mathrm{B}$ as (8.543±0.104)×${10}^{-2\mathrm{}}$ and (4.099±0.047)×${10}^{-2\mathrm{}}$ b, respectively.