Electron correlation theories

Pople J A, Krishnan R, Schlegel H B and Binkley J S 1978 Electron correlation theories and their application to the study of simple reaction potential surfaces int. J. Quantum Chem. 14 545-60... 

Electron Correlation Theories and Their Application to the Study of Simple Reaction Potential Surfaces. 

K. Raghavachari et al., A fifth-order perturbation comparison of electron correlation theories. Chem. Phys. Lett. 157, 479 183 (1989)... 

Raghavachari K, Trucks GW, Pople JA, Head-Gordon M (1989) A fifthorder perturbation comparison of electron correlation theories. Chem Phys Lett 157 479-483... 

Professor at the Technion Israel Institute of Science, in 2003 became Chair of the Department of Chemistry at the University of Massachusetts Boston, and in 2007 a Program Director at the NSF. He has contributed 270 peer reviewed papers and patents ranging from novel efficient solar semiconductor/electrochemical processes, to unusual batteries, to elucidation of complex equilibria and quantum electron correlation theory. 

J. A. Pople, R. Krishnan, H. B. Schlegel, and J. S. Binkley, hit. J. Quantum Chem., 14, 545 (1978). Electron Correlation Theories and Their Application to the Study of Simple Reaction Potential Surfaces. 

K. Raghavachari, G. W. Trucks, M. Head-Gordon, and J. A. Pople, Chem. Phys. Lett., 157, 479 (1989). A Fifth-Order Perturbation Comparison of Electron Correlation Theories. 

It is not possible in the limited space available here to give a detailed account of the many facets of modern multireference electron correlation theory. This would deviate too far from our current purpose. However, two aspects deserve special emphasis. 

In the course of the past decade several explanations have been put forward to account for the anomalous diffusion in bcc metals. The different models based on the presence of extrinsic vacancies (Kidson, 1963), on the temperature dependence of elastic constants (Aaronson and Shewmon, 1967), on dislocation enhanced diffusion (Peart and Askill, 1967) or on vacancy anharmonicity (Gilder and Lazarus, 1975) have been thoroughly discussed in the original and in the various review papers. Two additional models, the activated interstitial and, more recently, the w-embryo model, have been proposed as alternative explanations for anomalous bcc diffusion. These two models and their possible common interpretation on the basis of the Engel-Brewer electron correlation theory will be discussed in the next sub-section. 

Jiri Cizek introduced the (diagrammatic) CC method into electron correlation theory in a paper On the correlation problem in atomic and molecular systems. Calculation of wavefunction components in Ursell-type expansion using quantum-field theoretical methods, pubhshed in the Journal of Chemical Physics, 45, 4256 (1966). The book Three Approaches to Electron Correlation in Atoms (Yale University Press, New Haven, CT, and London 1970), edited by Oktay Sinanoglu and Keith A. Brueckner, contains several reprints of the papers that cleared the path toward the CC method. 

K. H. Marti, M. Reiher. New Electron Correlation Theories for Transition Metal Chemistry. Phys. Chem. Chem. Phys., 13... 

A 5th-Order Perturbation Comparison of Electron Correlation Theories. 

Recently, new multipole-based integral estimates (MBIE) have been introduced by Lambrecht and Ochsenfeld. They are simple, rigorous, and tight upper bounds to the two-electron integrals, and at the same time, they account for the 1/R decay behavior. Because these estimates can be appHed generally in quantum chemistry and are expected to be particularly important in view of electron-correlation theories for larger molecules, we briefly outHne the main ideas of this MBIE method. For a discussion of the latter in the context of electron correlation, see also the last section of this tutorial. 

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