Fundamentals of Self-Consistent-Field (SCF), Hartree-Fock (HF), Multi-Configuration (MC)SCF and Configuration Interaction (CI) schemes
1985; Elsevier BV; Volume: 2; Issue: 5 Linguagem: Inglês
10.1016/0167-7977(85)90009-7
ISSN1878-1004
AutoresR. McWeeny, Brian T. Sutcliffe,
Tópico(s)Advanced Chemical Physics Studies
ResumoThis report is concerned with the calculation of molecular wavefunctions and consist of two parts: the first provides an over-view of the development of various forms of self-consistent field (SCP) theory, from the early work of Hartee and collaborators (on atoms) up to the present day; while tehsecond turns to the systematic improvement of approximations at the Hartee-Fock (HF) level by the admission of configuration interaction (CI). The emphasis of the report is on the development of methodology, always in a form well adapted to computer implementation, but considerations of a purely computational nature are excluded. The aim is rather to provide a coherent review of one sector of a large and rapidly expanding area of computational physics - the calculation and use of high-precision electronic wavefunctions for molecules - and to provide a general introduction to other reports in this series. Part I deals first with the traditional approach to the problem of optimizing the orbitals in a one-determinant wavefunctions, as applied in the closed-shell, retricted and unrestricted forms of the HF approximation. This is followed by the introduction of second-quantization techniques and a more detailed discussion of solution methods. Part II is concerned with the general problem of constructing high-precision wavefunctions as truncated complete-set expansions containing thousands, sometimes millions, of terms. Recent progress is discussed, with emphasis on the exploitation of permutation and unitary group symmetries, the efficient evaluation of matrix elements, and the development of algorithms for solving very high order matrix eigenvalue equations.
Referência(s)