Analytic first and second derivatives for the CCSDT-n (n=1-3) models: a first step towards the efficient calculation of CCSDT properties

Authors
Gauss, J Stanton, JF
Citation
J. Gauss et Jf. Stanton, Analytic first and second derivatives for the CCSDT-n (n=1-3) models: a first step towards the efficient calculation of CCSDT properties, PHYS CHEM P, 2(10), 2000, pp. 2047-2060
Citations number
64
Categorie Soggetti
Physical Chemistry/Chemical Physics
Journal title
PHYSICAL CHEMISTRY CHEMICAL PHYSICS
ISSN journal
14639076 → ACNP
Volume
2
Issue
10
Year of publication
2000
Pages
2047 - 2060
Database
ISI
SICI code
1463-9076(2000)2:10<2047:AFASDF>2.0.ZU;2-L
Abstract
Analytic first and second derivatives of the energy are implemented for clo sed-shell systems described by the CCSDT-n (n = 1, 1b, 2 and 3) and CC3 ele ctron correlation models. A detailed discussion of the computational requir ements of these calculations is given, along with diagrammatic formulas for all relevant quantities. The method is applied to calculate the nuclear ma gnetic shielding of H2O, CO and N2O and the structure and properties of pro padienylidene.