Yanting Li, G. Gaigalas, Wenxian Li, Chongyang Chen, P. Jönsson
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Fine-Tuning of Atomic Energies in Relativistic Multiconfiguration Calculations
Ab initio calculations sometimes do not reproduce the experimentally observed energy separations at a high enough accuracy. Fine-tuning of diagonal elements of the Hamiltonian matrix is a process which seeks to ensure that calculated energy separations of the states that mix are in agreement with experiment. The process gives more accurate measures of the mixing than can be obtained in ab initio calculations. Fine-tuning requires the Hamiltonian matrix to be diagonally dominant, which is generally not the case for calculations based on jj-coupled configuration state functions. We show that this problem can be circumvented by a method that transforms the Hamiltonian in jj-coupling to a Hamiltonian in LSJ-coupling for which fine-tuning applies. The fine-tuned matrix is then transformed back to a Hamiltonian in jj-coupling. The implementation of the method into the General Relativistic Atomic Structure Package is described and test runs to validate the program operations are reported. The new method is applied to the computation of the 2s21S0−2s2p1,3P1 transitions in C III and to the computation of Rydberg transitions in B I, for which the 2s2p22S1/2 perturber enters the 2s2ns2S1/2 series. Improved convergence patterns and results are found compared with ab initio calculations.
AtomsPhysics and Astronomy-Nuclear and High Energy Physics
CiteScore
2.70
自引率
22.20%
发文量
128
审稿时长
8 weeks
期刊介绍:
Atoms (ISSN 2218-2004) is an international and cross-disciplinary scholarly journal of scientific studies related to all aspects of the atom. It publishes reviews, regular research papers, and communications; there is no restriction on the length of the papers. Our aim is to encourage scientists to publish their experimental and theoretical research in as much detail as possible. Full experimental and/or methodical details must be provided for research articles. There are, in addition, unique features of this journal: -manuscripts regarding research proposals and research ideas will be particularly welcomed. -computed data, program listings, and files regarding the full details of the experimental procedure, if unable to be published in a normal way, can be deposited as supplementary material. Scopes: -experimental and theoretical atomic, molecular, and nuclear physics, chemical physics -the study of atoms, molecules, nuclei and their interactions and constituents (protons, neutrons, and electrons) -quantum theory, applications and foundations -microparticles, clusters -exotic systems (muons, quarks, anti-matter) -atomic, molecular, and nuclear spectroscopy and collisions -nuclear energy (fusion and fission), radioactive decay -nuclear magnetic resonance (NMR) and electron spin resonance (ESR), hyperfine interactions -orbitals, valence and bonding behavior -atomic and molecular properties (energy levels, radiative properties, magnetic moments, collisional data) and photon interactions