The localized electrons detector as an ab initio representation of molecular structures

Abstract

The local single particle momentum is proposed as a localized-electrons detector (LED) that provides a direct three-dimensional representation of bonding interactions in molecules. It is given exclusively in terms of the electron density and its gradient. We show that the graphical representation of bonding interactions given by LED is consistent with the local curvatures of the electron density as given by the eigenvalues of the Hessian matrix, according to a local symmetry classification of the critical points here introduced. LED consistently complements the topological analysis of the electron density given by the quantum theory of atoms in molecules, by providing a graphical representation of the symmetry of the bonding interactions in molecular systems.

Exploring the electron density localization in single MoS2 monolayers by means of a localize-electrons detector and the quantum theory of atoms in molecules

“…19 Otherwise, a localized-electrons detector (LED) function defined in the quantum mechanics local moment representation and given exclusively in terms of the electron density and its gradient was recently proposed. 20,21 Using this LED function, an opposite pattern of the electron density localization for typical insulator cubic ceramic and good conductors transition metal materials, corroborating the Kohn conclusion, was been recently reported. 22 It was found that, for the elemental ceramic materials, the zone of low electron localization is very small and show areas containing the BCPs and the remainder CPs in separates regions of the space: the electrons are localized in separate areas and cannot move freely through the material.…”

“…LED isocontours show the same kind of symmetries 21 around the bond critical points that are given by the Laplacian of the electron density. Thus, it can show 3D-dimensionally the different kinds of bonding interactions identified by the topological analysis: the closed shell and the shared interactions.…”

“…21 The single particle kinetic energy provides the electronic localization of electron pairs in molecules, and hence its associated momentumP is an ideal localized electron pair detector. 20,21,24 It is given in terms of the electron density and its gradient,…”

“…The magnitude ofP depicts the regions where electrons are spatially confined in pairs, as in the case of bonding regions and atomic shells 21,24 and provides a direct three-dimensional representation of bonding interactions in molecules. LED isocontours show the same kind of symmetries 21 around the bond critical points that are given by the Laplacian of the electron density.…”

Structure of Hybrid Interpolymeric Complexes of Polyvinyl Alcohol and Halides of Second Group Elements

“…No remarkable change was noticed with respect to the standard calculation. To investigate the presence and nature of halide-PVA interactions, two different approaches were used: (1) topological analysis based on Bader's atoms in molecules (AIM) theory [21][22][23] and (2) the covalent interaction (NCI) index combined with the second derivative of the reduced density gradient along the second main axis of variation [24][25][26][27]. B3LYP[+GD3BJ] geometries and electron densities were used for this purpose.…”