ISSN:
0040-5744
Keywords:
Key words: Symmetry breaking
;
Correlation
;
DFI
;
HF instabilities
Source:
Springer Online Journal Archives 1860-2000
Topics:
Chemistry and Pharmacology
Notes:
Summary. The solution of both Hartree–Fock (HF) and Kohn–Sham (KS) equations is based on the variational principle. Exact wavefunctions would obey the same symmetry restrictions contained in the total hamiltonian. However, the variational principle does not guarantee these symmetry restrictions and the HF and KS solutions are not necessarily symmetric in spin and space. Spatial and spin symmetry broken solutions with lower energies than their restricted analogues are examined for C2 and Be2, in the context of the KS formalism. Comparison with UHF solutions shows that KS instabilities are far less pronounced. The main differences between HF and KS solutions are related to effects of electron correlation.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF01114989
Permalink
