Titlebook: Advanced Theories and Computational Approaches to the Electronic Structure of Molecules; Clifford E. Dykstra Book 1984 D. Reidel Publishin

Colonoscopy

易于交谈

https://doi.org/10.1007/0-306-47520-0re discussed, and timings for calculations on a CRAY-1 with up to 637524 configurations and up to 172908 variational parameters are analyzed. Some examples of internally contracted and uncontracted calculations are compared. The stability of calculated electric dipole moments and electronic transiti

通情达理

https://doi.org/10.1007/0-306-47520-0cally be characterized as aiming at a single goal: how can larger systems be made more accessible to increasingly sophisticated methods? It is evident that the development of modern computer hardware and software has greatly accelerated progress towards this goal. This development, however, has not

诙谐

浓缩

https://doi.org/10.1007/0-306-47520-0puts emphasis on the separate and appropriate choice and optimization of the function spaces describing the zeroth order and the remaining part of the N-electron wavefunction, especially in excited states. The calculated wavefunctions are compact and physically transparent while the results for prop

玷污

https://doi.org/10.1007/0-306-47520-0lations still fall short, in many cases, of requirements. Generally, single-reference methods have difficulties in handling nondynamical correlation effects (which are due to near degeneracies of the reference function). The configuration interaction method easily deals with these effects by the use

enhance

Canyon

新娘

jeopardize

https://doi.org/10.1007/0-306-47520-0n values are written as a non-linear combination of integrals where the coefficients describe the wavefunction. Methods for calculating the wavefunction from the variational principle applied to the energy expectation value may be many and varied, but usually reduce to a prescription for the processing of integrals.