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Lower bounds for the ground state energy for the PPP and Hubbard models of the benzene molecule

✍ Scribed by J. Číẑek; F. Vinette

Publisher
Elsevier Science
Year
1988
Tongue
English
Weight
490 KB
Volume
149
Category
Article
ISSN
0009-2614

No coin nor oath required. For personal study only.

✦ Synopsis

The optimized inner projection (OIP) technique, which is equivalent to the method of intermediate Hamiltonians (MIH), is applied to the PPP and Hubbard models of the benzene molecule. Both these methods are applicable since the electrostatic part of the PPP and Hubbard Hamiltonians is positive definite. Lower energy bounds are calculated using OIP and MIH for all values of the resonance integral /3. In this study, p plays the role of a coupling constant. The deviation of the OIP results from exact ones is smaller than 7% for all values of /I. The OIP results are also compared with the correlation energies obtained by other techniques.

The OIP method gives surprisingly good results even for small 181 values.

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