2005/12/31 by Wayne M. Itano, W. M. Itano
Decision Sciences · Physics and Astronomy · #Advanced Frequency and Time Standards #Atomic and Molecular Physics #Scientific Measurement and Uncertainty Evaluation #physics.atom-ph
paper · pdf · doi:10.1103/physreva.73.022510
published as Physical Review A 73, 022510 (2006) · 11 pages. Accepted by Physical Review A Added references. Corrected typos
arxiv created 2006/02/17 · openalex publication_date 2006/02/17 · arxiv updated 2009/12/01 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/30
Atomic quadrupole moments and hyperfine constants of the metastable states of , , , , and are calculated by the multiconfiguration Dirac-Hartree-Fock and relativistic configuration-interaction methods. For , the configuration is . For the other ions, the configuration consists of a single -electron outside a set of closed shells. Current interest in the quadrupole moments of these states is due to the fact that optical transitions of these ions may be useful as references for frequency standards. Energy shifts of the metastable states due to the interactions of the quadrupole moments with external electric field gradients are among the largest sources of error in these frequency standards. For the quadrupole moments, agreement is obtained to within about 10% with the available measurements. For the hyperfine constants, good agreement is obtained with measurements and with other calculations, except for the factors of the states of , , and , where the correlation effects are so large that they reverse the sign of the constant relative to the Dirac-Hartree-Fock value. As a test of the calculational methods, quadrupole moments and hyperfine constants are calculated for the states in isoelectronic neutral Au. This yields a value of the nuclear quadrupole moment .