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Updated: Jun 25, 2026

Computation of Atmospheric Concentrations of Molecular Clusters from ab initio Thermochemistry
Published on: April 8, 2020
Contracted Gaussian basis sets for Douglas-Kroll-Hess calculations: Estimating scalar relativistic effects of some
F E Jorge1, A Canal Neto, G G Camiletti
1Departamento de Física, Universidade Federal do Espírito Santo, 29060-900 Vitória, Brazil. jorge@cce.ufes.br
Abstract:
Douglas-Kroll-Hess (DKH) contracted Gaussian basis sets of double, triple, and quadruple zeta valence qualities plus polarization functions (XZP, X=D, T, and Q, respectively) for the atoms H-Ar and DZP and TZP for K-Kr are presented. They have been determined from the corresponding nonrelativistic basis sets generated previously by Jorge et al. We have recontracted the original XZP basis sets, i.e., the values of the contraction coefficients were reoptimized using the relativistic DKH Hamiltonian. The effect of DKH at the coupled-cluster level of theory on the ionization energy of some atoms and dissociation energy and geometric parameters for a sample of molecules is discussed. Our results were compared with theoretical and experimental values reported in the literature.
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