Symmetry eigenfunctions suitable for many-electron theories and calculations. I. Mainly atoms

Journal Article · Sat Sep 01 04:00:00 EDT 1973 · Int. J. Quant. Chem., v. 7, no. 5, pp. 927-944

DOI:https://doi.org/10.1002/qua.560070508· OSTI ID:4345503

Bunge, C F; Bunge, A

An interpretation of degenenate symmetry spaces associated with a given atomic or molecular configuration is presented, and the theory necessary for atomic applications is discussed in detail. Lowdin's symmetric projection operator for spin and orbital angular momentum is applied on a well defined sequence of Slater determinants. In this way a degenerate is space is divided into orthogonal invariant subspaces which can be classified according to internal couplings of angular momentum, A procedure is found which permits expression of each of these LS eigenfunctions as the smallest possible number of successively orthogonalized projected Slater determinants. In particular, minimum size Hartree -Fock interacting spaces (important in rapidly convergent correlation energy calculations) are obtained in their most compact form. An optimum partition of degenerate spaces of three and four excited (atomic or molecular) configurations is obtained in genenal. Interpretations, simplifications, and systematizations in atomic configuration interaction calculations are discussed in light of present results. (auth)

• Research Organization: Univ., Sao Paulo, Brazil
• Sponsoring Organization: USDOE
• NSA Number: NSA-29-022399
• OSTI ID: 4345503
• Journal Information: Int. J. Quant. Chem., v. 7, no. 5, pp. 927-944, Journal Name: Int. J. Quant. Chem., v. 7, no. 5, pp. 927-944; ISSN IJQCB
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

*ATOMS-- ELECTRONIC STRUCTURE
*MOLECULES-- ELECTRONIC STRUCTURE
ANGULAR MOMENTUM
COUPLING
EIGENFUNCTIONS
ELECTRONS
HARTREE-FOCK METHOD
MANY- BODY PROBLEM
MATHEMATICAL SPACE
N60500* --Physics (Atomic & Molecular)--Atomic Theory
ORBITAL ANGULAR MOMENTUM
PROJECTION OPERATORS
SLATER METHOD
SPIN
SYMMETRY