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:
We suggest the explicit transformation of the parametrized atomic φ-basis semiempirical Hamiltonian to the Löwdin λ basis. A nontrivial problem then arises concerning the transformation of the four-index electron interaction matrix Γ, for which parametrization is given in the φ basis, whereas the NDO approximation is introduced in the λ basis. The main result is that under the CNDO assumption the two-index Coulomb matrix can be transformed independently of other integrals of Γ. The explicit form of the transformation between the Coulomb matrix γ of parameters given in the φ basis and the Coulomb matrix λγ in the λ basis is found. The λγ calculated by this method differs only slightly from the result of the exact complicated four-index transformation. On the other hand the elements of γ and λγ may differ by several eV when overlap is significant.
Additional Material:
2 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/qua.560170211
