Premium
The half‐projected Hartree‐Fock model for computing thermally “forbidden” pericyclic reactions and biradical processes. I. Formulation and results for some singlet biradical species
Author(s) -
Olivella Santiago,
Salvador Jose
Publication year - 1990
Publication title -
international journal of quantum chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.484
H-Index - 105
eISSN - 1097-461X
pISSN - 0020-7608
DOI - 10.1002/qua.560370602
Subject(s) - wave function , singlet state , hamiltonian (control theory) , pericyclic reaction , slater determinant , mindo , hartree–fock method , chemistry , configuration interaction , diradical , quantum mechanics , physics , computational chemistry , atomic physics , electron , molecule , excited state , mathematics , atomic orbital , mathematical optimization
The possible use of a half‐projected Hartree‐Fock ( HPHF ) wave function correlating a single pair of electrons, being defined as a linear combination of two unrestricted Slater determinants which are identical except that all the α and β spin functions are interchanged, is investigated in relation to the computation of the potential energy surfaces involving singlet biradical or biradical‐like species. The results of calculations, within the framework of the MINDO /3 semiempirical Hamiltonian, for a number of prototypical biradical molecules indicate that, in general, the HPHF model provides a geometrical and energetical description that is equivalent to that obtained from a conventional two‐configuration self‐consistent‐field wave function.