Fock-space multireference coupled-cluster calculations of the hyperfine structure of isoelectronic33S−and35,37Cl

Abstract

Due to its flexibility and possible systematic improvement, the Fock-space (FS) multireference coupled-cluster (MRCC) method remains a very important tool for the computation of energy differences of spectroscopic interest. In the present work, the FS MRCC method for the electron detachment process has been applied to determine the magnetic hyperfine constant ${A}_{J}$ and nuclear quadrupole moments $Q$ (related to electric hyperfine constant ${B}_{J}$) for the lowest multiplets of ${}^{33}$S${}^{\ensuremath{-}}$, ${}^{35}$Cl, and ${}^{37}$Cl with Dirac-Fock orbitals. In addition, we also report ${}^{2}$${P}_{3/2}$([Ne]$3{s}^{2}3{p}^{5}$) $\ensuremath{\rightarrow}$ ${}^{2}$${P}_{1/2}$([Ne]$3{s}^{2}3{p}^{5}$) magnetic dipole transition matrix element and electron affinity of ${}^{35}\mathrm{Cl}$ (i.e., ionization energy of Cl${}^{\ensuremath{-}}$). Calculated properties are in very good agreement with the available new standard or reference values.