Formulae for the analytical differentiation of the energy contribution due to triple excitations (T) within quadratic conftguration interaction (QCI) theory are derived. Combining these formulae with previously derived formulae for the evaluation of analytical first derivatives for QCI theory with s
Analytical evaluation of energy gradients in quadratic configuration interaction theory
✍ Scribed by Jürgen Gauss; Dieter Cremer
- Publisher
- Elsevier Science
- Year
- 1988
- Tongue
- English
- Weight
- 454 KB
- Volume
- 150
- Category
- Article
- ISSN
- 0009-2614
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✦ Synopsis
Analytical formulae for the energy gradient within the quadratic configuration interaction singles and doubles (QCISD) method are derived and their implementation is discussed. The method is applied to 6-3 lG(d) computations on H,O and HzOz.
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