Computational Chemistry

concept is clearly related to the dipole moment: in a diatomic (for simplicity) molecule one expects the negative end of the dip ...

this criterion and Lewis structures the C/C bond order in ethane is 1, in ethene 2, and in ethyne 3, in accordance with the clas ...

overlap integrals are also unity, since the basis functions are normalized (cf. Section 4.4.1.2). In the Mulliken scheme each el ...

“electron density sum” in Eq. (5.210). Now if there arenielectrons in MOci, then the contributions ofcito the electron populatio ...

depends on the electronegativity difference between the atoms on whichfrand fsreside, with the more electronegative atom getting ...

ðPSÞ¼ ðPSÞ 11 ðPSÞ 12 ðPSÞ 13 (((ðPSÞ 1 m ðPSÞ 21 ðPSÞ 22 ðPSÞ 23 (((ðPSÞ 2 m ... ... ((( ... ðPSÞm 1 ðPSÞm 2 ðPSÞm 3 (((ðPSÞmm ...

5.5.4.3 An Example of Population Analysis: H–Heþ As a simple illustration of the calculation of atom charges and bond orders, co ...

Nr¼N 2 ¼nrþ 1 2 X s 6 ¼r nr=s¼n 2 þ 1 2 ðn 2 = 1 Þ¼ 1 : 2864 þ 1 2 ð 0 : 5114 Þ¼ 1 : 5421 The sum of all theNron He has only one ...

been used particularly in inorganic chemistry [ 262 ]. The most popular method of population analysis now is probably Weinhold’s ...

use of visualization of the ESP is discussed inSection 5.5.6). Values of Mulliken and L€owdin bond orders, and Mulliken, natural ...

risen to supremacy with MO theory) and summarized the essential concepts of AIM theory [ 270 ]. Bader reviewed the subject a dec ...

falls toward a minimum (Fig.5.40). Viewing the electron distribution in terms of#r rather thanris useful because it more easily ...

Moving along the internuclear line we find a point in a saddle-shaped region, analogous to a transition state, where the surface ...

For the#r/qsurface of Fig.5.41the number of positive and negative eigenva- lues for a nuclear critical point are 3 and 0, and fo ...

and meeting S at the bond critical point. The electron density defines agradient vector field, the totality of thetrajectoriesea ...

orderrbcan be defined in terms of the electron density, and the bond orderbABfor two particular atoms A and B is then defined by ...

5.5.5.1 UV Spectra Ultraviolet spectra result from the promotion of an electron in an occupied MO of a ground electronic state m ...

computational work on NMR spectra has focussed on calculating the shielding (magnetic field strength needed for the transition r ...

an occupied orbital and in the other (EA) addition of an electron to a virtual (or a half-occupied) orbital. The IE for an orbit ...

typical covalent bond. Molecules often don’t have a “real” electron affinity, fre- quently ejecting an added electron spontaneou ...