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Integral approximations on the basis of semiorthogonalized orbitals

โœ Scribed by Hiroshi Kashiwagi

Publisher
John Wiley and Sons
Year
1976
Tongue
English
Weight
366 KB
Volume
10
Category
Article
ISSN
0020-7608

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โœฆ Synopsis

Abstract

Semiorthogonalized orbitals are introduced as a basis of approximate ab initio molecular calculations. The semiorthogonalized orbitals are obtained from the usual overlapping atomic orbitals by means of a generalized Lรถwdin transformation. The new orbitals are characterized by two features: many overlaps between them are zero, and they are close to their corresponding initial atomic orbitals. On the basis of the semiorthogonalized orbitals, a scheme of integral approximations is proposed which allows one to carry out approximate ab initio calculations with less computational efforts and thus offers a possibility to perform calculations on much bigger molecules with limited computational facilities. Results are presented for model calculations on the anthracene ฯ€โ€electron system. Orbital energies and electron distribution are quite close to the rigorously calculated values.

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