Studies of molecular states using spin-coupled valence-bond theory

摘要: The spin-coupled wavefunction for an N-electron system is described, and the technical aspects (formation of density matrices, energy minimisation, generation virtual orbitals) briefly outline. physical interpretation provided by this model illustrated calculations on potential-energy surface C++ H2 system. theory quantitatively refined at valence-bond stage. Results CH+, LiHe+ BH+2 are presented which show that, least these systems, chemical accuracy may be attained with 200–500 non-orthogonal ‘spin-coupled structures’(configuration state functions). Each eigenvector dominated one or two such structures, thus providing visuality without sacrificing accuracy.