Molecules electronic structure of

The Mean-Field Model, Which Forms the Basis of Chemists Pictures of Electronic Structure of Molecules, Is Not Very Accurate... 

I. Shavitt, Advanced Theories and Computational Approaches to the Electronic Structure of Molecules C. E. Dykstra, Ed., 185, Reidel, Dordrecht (1984). 

R. S. Mulliken (Chicago) fundamental work concerning chemical bonds and the electronic structure of molecules by the molecular orbital method. 

Valence bond model Model of the electronic structure of molecules in which electrons are assigned to orbitals, pure or hybridized, of individual atoms, 185-186... 

Arai, T., J. Chem, Phys. 26, 435, New approach to the quantum-mechanical analysis of the electronic structure of molecules. The method of deformed atoms in molecules. A modification of Moffitt s method. 

The Calculation of Matrix Elements for Lewis Electronic Structures of Molecules... 

Three years ago it was pointed out2 that observed values of interatomic distances provide useful information regarding the electronic structures of molecules and especially regarding resonance between two or more valence bond structures. On the basis of the available information it was concluded that resonance between two or more structures leads to interatomic distances nearly as small Us the smallest of those for the individual structures. For example, in benzene each carbon-carbon bond resonates about equally between a single bond and a double bond (as given by the two Kekul6 structures) the observed carbon-carbon distance, 1.39 A., is much closer to the carbon-carbon double bond distance, 1.38 A., than to the shrgle bond distance, 1.54 A. 

The Use of the Interatomic Distance Function in Discussing the Electronic Structure of Molecules.—The observed interatomic distances listed in Table II are interpreted with the aid of the curve of Fig. 1 to lead to the assignment of fractional double bond character as given in the last column. It is seen that a single bond between conjugated double bonds (cyclopentadiene) or... 

Mulliken, R.S. Electronic Structures of Molecules. XI. Electroaffinity, Molecular Orbitals and Dipole Moments J. Chem. Phys. 1935, 3, 573-585. 

Parr, R. G., Yang, W., 1995, Density-Functional Theory of the Electronic Structure of Molecules , Annu. Rev. Phys. Chem., 46, 701. 

J. W, Linneu, The Electronic Structure of Molecules, 1964, Methuen, London. 

Linnett, J. W. (1964). The electronic structure of molecules. London Methuen. 

Calculations of the electronic structure of molecules, crystals and surfaces are often performed in atomic units. They are defined by setting the most important constants equal to unity h — eo — me — 1, where me is the electronic mass. The Coulomb law is written in electrostatic units V(r) = q/r, so that the time-independent Schrodinger equation for the hydrogen atom takes on the simple form ... 

One requires both these perspectives to tackle all issues in the theory of electronic structure of molecules and their chemical reactivity. The wave function and... 

Clearly, if the GHOs are to be used in a theory of valence we must establish some rules for the approximate contraction (or expansion) factor which will enable us to avoid the tedious business of non-linear optimisation processes. This is work for the future — for the moment we simply investigate some of the properties of the GHOs when used to investigate the electronic structure of molecules at equilibrium geometry. 

In the first place, we have been studying those parts of the theory of the electronic structure of molecules which bear on a theory of valence. That is we are not attempting to present a theory of molecular electronic structure, but an approximate theory of valence. The latter is but a small part of the former. In particular we are (in the main) concerned with localised systems of electrons in their ground states the theory... 

Linus Pauling, "The Nature of the Chemical Bond. III. The Transition from One Extreme Bond Type to Another," JACS 54 (1932) 981003 Linus Pauling, "Interatomic Distances in Covalent Molecules and Resonance between Two or More Lewis Electronic Structures," Proc.NAS 18 (1932) 293297 Linus Pauling, "The Calculation of Matrix Element for the Lewis Electronic Structure of Molecules,"... 

What was the distinction between quantum chemistry and chemical physics After the Journal of Chemical Physics was established, it was easy to say that chemical physics was anything found in the new journal. This included molecular spectroscopy and molecular structures, the quantum mechanical treatment of electronic structure of molecules and crystals and the problem of chemical binding, the kinetics of chemical reactions from the standpoint of basic physical principles, the thermodynamic properties of substances and calculation by statistical mechanical methods, the structure of crystals, and surface phenomena. 

Mulliken, who published the first articles in his series, "Electronic Structures of Molecules and Valence," in Physical Review, was not keen initially on the new journal but nonetheless shifted his series to the Journal of... 

Molecular photoelectron spectroscopy (PES) is widely used to study the electronic structure of molecules, and compounds can be characterized by their PE spectra. In this chapter the results of ultraviolet PE spectroscopic (UPS) studies of molecules which incorporate amino, nitroso or nitro groups will be summarized. 

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