Journal ArticleDOI
Contribution of triple substitutions to the electron correlation energy in fourth order perturbation theory
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This article is published in Journal of Chemical Physics.The article was published on 1980-04-01. It has received 1148 citations till now. The article focuses on the topics: Perturbation theory & Electronic correlation.read more
Citations
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A fifth-order perturbation comparison of electron correlation theories
TL;DR: In this paper, a new augmented version of coupled-cluster theory, denoted as CCSD(T), is proposed to remedy some of the deficiencies of previous augmented coupledcluster models.
Journal ArticleDOI
Self‐consistent molecular orbital methods 25. Supplementary functions for Gaussian basis sets
TL;DR: In this paper, a modified basis set of supplementary diffuse s and p functions, multiple polarization functions (double and triple sets of d functions), and higher angular momentum polarization functions were defined for use with the 6.31G and 6.311G basis sets.
Journal ArticleDOI
Quadratic configuration interaction. A general technique for determining electron correlation energies
TL;DR: In this article, a general procedure for calculation of the electron correlation energy, starting from a single Hartree-Fock determinant, is introduced, and the relation of this method to coupled-cluster (CCSD) theory is discussed.
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Optimization of equilibrium geometries and transition structures
TL;DR: In this paper, a modified conjugate gradient algorithm for geometry optimization is presented for use with ab initio MO methods, where the second derivative matrix rather than its inverse is updated employing the gradients.
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Gaussian-3 (G3) theory for molecules containing first and second-row atoms
TL;DR: In this paper, a new theoretical procedure based on ab initio molecular-orbital theory for the calculation of molecular energies of compounds containing first (Li-F) and second row (Na-Cl) atoms is presented.
References
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Journal ArticleDOI
The influence of polarization functions on molecular orbital hydrogenation energies
P. C. Hariharan,John A. Pople +1 more
TL;DR: In this paper, a split-valence extended gaussian basis set was used to obtain the LCAO-MO-SCF energies of closed shell species with two non-hydrogen atoms.
Journal ArticleDOI
Note on an Approximation Treatment for Many-Electron Systems
Chr. Møller,Milton S. Plesset +1 more
TL;DR: In this article, a perturbation theory for treating a system of n electrons in which the Hartree-Fock solution appears as the zero-order approximation was developed, and it was shown by this development that the first order correction for the energy and the charge density of the system is zero.
Journal ArticleDOI
Accuracy of AH n equilibrium geometries by single determinant molecular orbital theory
P.C. Hariharan,John A. Pople +1 more
TL;DR: In this paper, a simple level of ab initio molecular orbital theory with a split-valence shell basis with d-type polarization functions was used to predict equilibrium geometries for the ground and some low-lying excited states of AHn molecules and cations where A is carbon, nitrogen, oxygen or fluorine.
Journal ArticleDOI
Theoretical models incorporating electron correlation
TL;DR: In this paper, the perturbation approach originally introduced by Moller and Plesset, terminated at finite order, is compared from the point of view of requirements for theoretical chemical models.
Journal ArticleDOI
Approximate fourth-order perturbation theory of the electron correlation energy
R. Krishnan,John A. Pople +1 more
TL;DR: In this article, an approximate fourth-order expression for the electron correlation energy in the Moller-Plesset perturbation scheme is proposed, which takes into account all the contributions to the fourthorder energy neglecting only those of the triple-substituted determinants.