Electrostatic potential, molecular interactive electronic charge distributions

Electron distribution governs the electrostatic potential of molecules. The electrostatic potential describes the interaction of energy of the molecular system with a positive point charge. Electrostatic potential is useful for finding sites of reaction in a molecule positively charged species tend to attack where the electrostatic potential is strongly negative (electrophilic attack). 

Polarization Potential. Afimction describing the energy of electronic relaxation of a molecular charge distribution following interaction with a point positive charge. The polarization potential may be added to the Electrostatic Potential to provide a more accurate account of the interaction of a point-positive charge and a molecule. 

The mutual polarization process between the solute and the polarizable medium is obtained by solving a system of two coupled equations, i.e., the QM Schrodinger equation for the solute in presence of the polarized dielectric, and the electrostatic Poisson equation for the dielectric medium in presence of the charge distribution (electrons and nuclei) of the solute. The solute occupies a molecular shaped cavity within the dielectric continuum, whose polarization is represented by an apparent surface charge (ASC) density spread on the cavity surface. The solute-solvent interaction is then represented by a QM operator, the solvent reaction potential operator, Va, corresponding to the electrostatic interaction of the solute electrons and nuclei with the ASC density of the solvent. 

The symbol V is often associated with the electrical potential in the literature, but U is employed here so as not to conflict with the volume descriptor. Another aspect of chemical reactivity involves the molecular electrostatic potential (MEP). The MEP is the interaction energy between a unit point charge and the molecular charge distribution produced by the electrons and nuclei. The electrostatic potential, U r), at a point, r, is defined by Eq. [13]. 

Such an expression has previously been used for comparative purposes, for the study of interaction between two molecular species, by computing the electrostatic potential of the first partner and by assuming some point charge model as representative of the charge distribution of the second partner. We also plan to extend this concept in a more subtle way by using an electron density contour map to describe the charge distribution of the second partner as a function of the space surrounding this second partner. 

A promising lead in the estimation of electrostatic interactions is the use of electrostatic molecular potentials [24]. This method simulates the coulombic contribution to the intermolecular interaction by substituting appropriately chosen point charges, which may be fractional, to replace actual neighbouring molecules. The potential is a function of the electronic distribution and the position of the nuclei in the molecule and is computed from molecular wave functions. It is the basic premise of the use of electrostatic potentials that - pol> - Ct and fi disp much less important than electrostatic effects in determining structural features of complex formation. The deformations of the special charge distribution of a set of atoms bound together to form a molecule are quite complex and the electrostatic potential, like all other... 

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