Electrostatic potentials and reactivities

Nucleophilic atoms can also be identified by inspection of electrostatic potential maps. Reactive sites appeal as negative electrostatic potentials. Examine electrostatic potential maps for trimethylamine, methyl fluoride, and phenol. Identify the most nucleophilic atom in each molecule. Are these the same as you identified above using Lewis structures Are all sides of the nucleophilic atoms equally electron rich, or only particular regions ... 

Politzer, P., and I. S. Murray. 1991. Molecular Electrostatic Potentials and Chemical Reactivity. In Reviews in Computational Chemistry. K. B. Lipkowitz and D. B. Boyd, eds. VCH Publishers, New York. 

Peter Politzer and Jane S. Murray, Molecular Electrostatic Potentials and Chemical Reactivity. 

This chapter introduces and illustrates isosurface displays of molecular orbitals, electron and spin densities, electrostatic potentials and local ionization potentials, as well as maps of the lowest-unoccupied molecular orbital, the electrostatic and local ionization potentials and the spin density (on top of electron density surfaces). Applications of these models to the description of molecular properties and chemical reactivity and selectivity are provided in Chapter 19 of this guide. 

Politzer P, Murray JS. Molecular electrostatic potentials and chemical reactivity. In Lipkowitz KB, Boyd DB, eds. Reviews in Computational Chemistry. Vol. 2. New York VCH, 1991 273-312. 

P. R. Lawrence, T. R. Proctor, and P. Politzer, Int. ]. Quantum Chem., 26, 425 (1984). Reactive Properties of rrans-Dichloro-oxirane in Relation to Carcinogenicities of Vinyl Chloride and truns-Dichloro-ethylene. J. S. Murray and P. Politzer, Int. J. Quantum Chem., 31, 569 (1987). A Computational Study of Isomerization Equilibria Relation to Vinyl Chloride Carcinogenicity. P. Politzer and J. S. Murray, in Reviews in Computational Chemistry, Vol. 2, K. B. Lipkowitz and D. B. Boyd, Eds., VCH Publishers, New York, 1991, pp. 273—312. Molecular Electrostatic Potentials and Chemical Reactivity. 

An extension of the Hohenberg-Kohn theorems to an arbitrary excited electronic state has not been possible till date. It has been possible only for the lowest state of a given symmetry [45] and for the ensemble of states [46], It may be anticipated from the principles of maximum hardness and minimum polarizability that a system would become softer and more polarizable on electronic excitation since it is generally more reactive in its excited state than in the ground state. Global softness, polarizability, and several local reactivity parameters p(r, t), Vp, —V2p,/(r), electrostatic potential, and quantum potential have been calculated [25] for different atoms, ions, and molecules for the lowest energy state of a particular symmetry and various complexions of a two-state ensemble. It has been observed that a system is harder and less polarizable in its ground state than in its excited states, and an increase in the excited state contribution in a two-state ensemble makes the system softer and more polarizable. Surface plots of different local quantities reveal an increase in reactivity with electronic excitation. 

Murray JS, Brinck T, Grice ME, Politzer P. Correlations between molecular electrostatic potentials and some experimentally-based indices of reactivity. J Mol Struct (Theochem) 1992 256 29 45. 

P. Politzer and K. C. Daiker, The Force Concept in Chemistry. B. M. Deb, Ed., Van Nostrand, New York, 1981. See also, P. Politzer and J. S. Murray, this volume. Molecular Electrostatic Potentials and Chemical Reactivity. 

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