Note on an Approximation Treatment for Many-Electron Systems
Chr. Møller,Milton S. Plesset +1 more
Reads0
Chats0
TLDR
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.Abstract:
A perturbation theory is developed for treating a system of n electrons in which the Hartree-Fock solution appears as the zero-order approximation. It is shown by this development that the first order correction for the energy and the charge density of the system is zero. The expression for the second-order correction for the energy greatly simplifies because of the special property of the zero-order solution. It is pointed out that the development of the higher approximation involves only calculations based on a definite one-body problem.read more
Citations
More filters
Journal ArticleDOI
A benchmark theoretical study of the electronic ground state and of the singlet-triplet split of benzene and linear acenes
TL;DR: Singlet-triplet (S(0)-T(1) energy gaps can be very accurately determined by applying the principles of a focal point analysis onto the results of a series of single-point and symmetry-restricted calculations employing correlation consistent cc-pVXZ basis sets and single-reference methods of improving quality.
Book ChapterDOI
Chapter 10 The Effective Fragment Potential: A General Method for Predicting Intermolecular Interactions
TL;DR: The effective fragment potential (EFP) as mentioned in this paper is an approach for studying intermolecular interactions, which can generally not account for bond breaking, but can, in principle, account for a range of intermolescular interactions.
Journal ArticleDOI
Where does the planar-to-nonplanar turnover occur in small gold clusters?
Ryan M. Olson,Sergey A. Varganov,Mark S. Gordon,Horia Metiu,Steeve Chrétien,Piotr Piecuch,Karol Kowalski,Stanisław A. Kucharski,Monika Musiał +8 more
TL;DR: Several levels of theory, including both Gaussian-based and plane wave density functional theory (DFT), second-order perturbation theory (MP2), and coupled cluster methods (CCSD(T)), are employed to study Au6 and Au8 clusters.
Journal ArticleDOI
N[bond]C(alpha) bond dissociation energies and kinetics in amide and peptide radicals. Is the dissociation a non-ergodic process?
TL;DR: Transition state theory rate constants for dissociations of N[bond]C(alpha) bonds in aminoketyl radicals and cation-radicals indicate an extremely facile reaction that occurs with unimolecular rate constants >10(5) s-1 in species thermalized at 298 K in the gas phase.
Journal ArticleDOI
Quantum Mechanical Methods and the Interpretation and Prediction of Pericyclic Reaction Mechanisms
TL;DR: The computational study of pericyclic reactions, an important general class of organic reactions, now provides information about the transition structures of these processes with chemical accuracy, as judged by comparisons with experimental data, such as activation energies, substituent effects on rates, and kinetic isotope effects.