ISSN:
0020-7608
Keywords:
Computational Chemistry and Molecular Modeling
;
Atomic, Molecular and Optical Physics
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
N molecular orbitals are transformed to K(≦N) molecular orbitals, which are appropriate for an orbital optimization by two-by-two orthogonal rotations among themselves. This transformation is determined by using the second-order structure of the variational energy surface. The optimum K/2 rotation angles are exactly determined. This helps to ensure the reliability of convergence. K/2 two-by-two rotations are repeated among these K transformed orbitals. Then, two-electron molecular integrals are calculated by transformations among only 16 elements and by a permutation among K4/8 elements. Calculational time is considerably reduced compared with that of more usual transformations. Test calculations have been carried out on the ground state of CO. It shows that this procedure brings the calculation to the local region rapidly and reliably.
Additional Material:
2 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/qua.560280204
