dorsal/arxiv
View SchemaThe nonrelativistic limit of Dirac-Fock codes: the role of Brillouin configurations
| Authors | Paul Indelicato, Eva Lindroth, Jean-Paul Desclaux |
|---|---|
| Categories | |
| ArXiv ID | physics/0408049 |
| URL | https://arxiv.org/abs/physics/0408049 |
| DOI | 10.1103/PhysRevLett.94.013002 |
| Journal | Physical Review Letters 94 (2005) 013002 |
Abstract
We solve a long standing problem with relativistic calculations done with the widely used Multi-Configuration Dirac-Fock Method (MCDF). We show, using Relativistic Many-Body Perturbation Theory (RMBPT), how even for relatively high-$Z$, relaxation or correlation causes the non-relativistic limit of states of different total angular momentum but identical orbital angular momentum to have different energies. We show that only large scale calculations that include all single excitations, even those obeying the Brillouin's theorem have the correct limit. We reproduce very accurately recent high-precision measurements in F-like Ar, and turn then into precise test of QED. We obtain the correct non-relativistic limit not only for fine structure but also for level energies and show that RMBPT calculations are not immune to this problem.
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"abstract": "We solve a long standing problem with relativistic calculations done with the\nwidely used Multi-Configuration Dirac-Fock Method (MCDF). We show, using\nRelativistic Many-Body Perturbation Theory (RMBPT), how even for relatively\nhigh-$Z$, relaxation or correlation causes the non-relativistic limit of states\nof different total angular momentum but identical orbital angular momentum to\nhave different energies. We show that only large scale calculations that\ninclude all single excitations, even those obeying the Brillouin\u0027s theorem have\nthe correct limit. We reproduce very accurately recent high-precision\nmeasurements in F-like Ar, and turn then into precise test of QED. We obtain\nthe correct non-relativistic limit not only for fine structure but also for\nlevel energies and show that RMBPT calculations are not immune to this problem.",
"arxiv_id": "physics/0408049",
"authors": [
"Paul Indelicato",
"Eva Lindroth",
"Jean-Paul Desclaux"
],
"categories": [
"physics.atom-ph"
],
"doi": "10.1103/PhysRevLett.94.013002",
"journal_ref": "Physical Review Letters 94 (2005) 013002",
"title": "The nonrelativistic limit of Dirac-Fock codes: the role of Brillouin configurations",
"url": "https://arxiv.org/abs/physics/0408049"
},
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