Electronic charge density Laplacian

The contour maps of the Laplacian distribution of the electronic charge density... 

C) Relief map of the negative Laplacian of the charge density, -V2p, of the chlorine molecule. One can notice three depletions of the electron charge density in the region perpendicular to the bond, and along the interatomic axis, for the colinear approach at the both ends. 

Contour values for maps of the electronic charge density and of the Laplacian... 

The contours of the Laplacian of the electronic charge density (dashed contours VV < 0, solid contours VV > 0) increase and decrease from a zero contour in steps + 2 X 10", + 4 X 10", + 8 X 10", beginning with n = — 3 and increasing in steps of unity. The innermost solid contour encompassing a nucleus with Z > 1 encloses the innermost region of charge concentration. 

The Laplacian of the electronic charge density (V p(r)) describes two extreme situations, hi the first p r) is locally concentrated (V p(r) < 0) and in the second it is locally depleted (V p(r) > 0). Thus, a value of V p(r) < 0 at a BCP is unambiguously related to a covalent bond, showing that a sharing of charge has taken place. In a closed-shell interaction a value of V p(r) > 0 is expected, as found in noble gas repulsive states, in ionic bonds, in hydrogen bonds and in van der Waals molecules. 

Table 3 The electronic charge density (,p(r)), its Laplacian (y p(r)). ellipticity (c), electronic energy density E (r) and (Ai /I3), at the different theoretical levels for the P-0 and N-0 BCPs of structures 1-4...

Laplacian is related to the electronic energy density E(r) of the charge distribution, defined as... 

Shutov et al. carried out density functional theory (DFT) calculations on E[N(SiMe3)CH2CH2]3N (E = P, Sb, Bi) up to the PBE level of theory <2002IC6147>. The structural data obtained from geometry optimization on antimony and bismuth derivatives reproduced experimental trends, that is, a decrease in the Ndat-E distance from Sb to Bi. The values of electron density in Ndat-E critical point and the Laplacian of charge density for the azabismatrane indicated that a closed-shell interaction existed between Bi atom and Ndat atom. 

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