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Manuscript Title: CESD97 - a revised version to expand jj-coupled symmetry functions into determinants.
Authors: S. Fritzsche, I.P. Grant
Program title: CESD97
Catalogue identifier: ADCB_v2_0
Distribution format: tar.gz
Journal reference: Comput. Phys. Commun. 103(1997)277
Programming language: Fortran.
Computer: IBM RS 6000-520.
Operating system: IBM AIX 3.2.5+.
Word size: 32
Keywords: Atomic physics, Structure, Configuration, Decoupling, Determinant, Jj-coupling, Multiconfiguration Dirac-fock, Relativistic.
Classification: 2.1.

Subprograms used:
Cat Id Title Reference
ADCU_v1_0 GRASP92 CPC 94(1996)249
ADEJ_v1_0 REOS CPC 99(1997)323

Nature of problem:
The jj-coupled symmetry basis functions of the atomic structure program GRASP92 [1] are expanded into Slater determinants.

Reasons for new version:
The revised version GRASP92 [1] has been considerably modified in order to facilitate systematic investigations in the multiconfiguration Dirac- Fock (MCDF) model. Important changes concern the dynamic allocation of all larger arrays, file handling as well as the interactive execution. These modifications have now also been applied to the CESD component. Systematic MCDF calculations often require single and double excitations into subshells with (one-electron) angular momenta larger than j>7/2. Like GRASP92, our revised program now supports double occupation of such high-j subshells for all corresponding principal quantum numbers.

Restrictions:
The maximal number of electrons in subshells with J>=9/2 is two. This is consistent with the GRASP92 package, since for those large one- electron angular momenta, j, additional quantum numbers are needed to classify arbitrary antisymmetric subshell states. The present version is still limited to a maximal number of five open subshells for each single configuration state function (CSF) which, however, can easily be extended to some larger value. This version supersedes the original version. Apart from necessary modifications of various input and output formats, CESD97 supports an interactive control as well as the dynamic allocation of just that size of memory as it is required to perform some computation. Furthermore, no other restrictions than in GRASP92 itself now apply for the coupling of the one-electron orbitals.

Unusual features:
CESD97 is designed to be part of the RATIP package [3] for calculating relativistic atomic transition and ionization properties. As it is appropriate for large CSF lists, CESD97 applies dynamic allocation for all arrays related to the representation of the atomic states. The pointer data type of FORTRAN is used to allow for run-time allocation. Thus, neither the number of CSF nor the number of determinants is formally restricted by any array dimension. Other dimensions which need not to be modified in standard applications are defined via PARAMETER statements.

Running time:
To execute the test data took 8 seconds on a RS 6000-520.

References:
[1] F.A. Parpia, C.F. Fischer and I.P. Grant, Comput. Phys. Commun. 94(1996)249.
[2] S. Fritzsche and I.P. Grant, Comput. Phys. Commun. 92(1995)111.
[3] S. Fritzsche and C. Froese Fischer, Comput. Phys. Commun. 99(1997)323.