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New Version: Grasp2K Relativistic Atomic Structure Package



P. Jonsson, G. Gaigalas, J Bieron, Charlotte F. Fischer, I. P. Grant


A revised version of Grasp2K [P. Jonsson, X. He, C. Froese Fischer, and I.P. Grant, Comput. Phys. Commun. 177 (2007) 597] is presented. It supports earlier non-block and block versions of codes as well as a new block version in which the njgraf library module [A. Bar-Shalom and M. Klapisch, Comput. Phys. Commun. 50 (1988) 375] has been replaced by the librang angular package developed by G. Gaigalas based on the theory of [G.A. Gaigalas, Z.B. Rudzikas, and C. Froese Fischer, J. Phys. B: At. Mol. Phys. 30 (1997) 3747, G. Gaigalas, S. Fritzsche, and I.P. Grant, Comput. Phys. Commun. 139 (2001) 263]. Tests have shown that errors encountered by njgraf do not occur with the new angular package. The three versions are denoted as v1, v2, v3, respectively. In addition, in v3, the coecients of fractional parentage have been extended to j = 9=2, making calculations feasible for the lanthanides and actinides. Changes in v2 include minor improvements. For example, the new version of rci2 may be used to compute QED corrections only from selected orbitals. In v3 a new program, jj2lsj, reports the percentage composition of the wave function in LSJ and the program rlevels has been modi ed to report the CSF with the largest coecient of an LSJ expansion. The bioscl2 and bioscl3 application programs have been modi ed to produce a le of transition data with one record for each transition in the same format as in Atsp2K [C. Froese Fischer, G. Tachiev, G. Gaigalas, and M.R. Godefroid, Comput. Phys. Commun. 176 (2007) 559], that identi es each atomic state by the total energy and a label for the CSF with the largest expansion coecient in LSJ intermediate coupling. All versions of the codes have been adapted for 64-bit computer architecture.
Computer Physics Communications


atomic structure calculations, Breit interaction, con figurationinteraction, correlation, Dirac theory, energy levels, hyperfi ne structure, isotopeshift, jj coupling, LSJ intermediate coupling, multicon figurationDirac-Hartree-Fock, nuclear volume e ffects, QED, relativistic eff ects in atoms, specfi c mass shift, transverse photon interactions, transition probabilities, Zeemane ffect


Jonsson, P. , Gaigalas, G. , Bieron, J. , Fischer, C. and Grant, I. (2013), New Version: Grasp2K Relativistic Atomic Structure Package, Computer Physics Communications, [online], (Accessed September 26, 2023)
Created February 19, 2013, Updated July 3, 2023