Fukui Indices from Perturbed Kohn−Sham Orbitals and Regional Softness from Mayer Atomic Valences

Abstract

Chemical reactivity descriptors are computed by the use of three alternative approaches derived within the framework of density functional theory. These schemes consider the computation of orbital Fukui indices, where all valence orbitals are taken into account; the Fukui indices of each atom in the molecule from the atomic resolved hardness matrix; and the atom in molecule softnesses, expressed in mixed LCAO representation of second quantization as functions of Mayer atomic valences. The hardness matrix is constructed from the Kohn-Sham orbitals by the use of the fractional occupation number concept and Janak's extension of density functional theory. The site reactivity of molecules involved in radical attack reactions of some substituted olefins and isocyanide addition to dipolarophiles is rationalized in terms of the orbital and atomic resolved reactivity indices. The reactivity descriptors of thiophene, furane, and pyrrole are also reported and discussed. In addition, the nucleophilic attack on the allyl coordinated to the electronically asymmetric [Pd(phosphine)-(imine)] fragment was considered.

Novel cinnamic acid/4-aminoquinoline conjugates bearing non-proteinogenic amino acids: Towards the development of potential dual action antimalarials

“…This study was based on the assumption that the vinyl bond would act as the Michael acceptor in the ligand's irreversible binding to the falcipain catalytic Cys. Atomic Fukui indices (fþ), derived from Natural Bond Order (NBO) population analysis of the neutral compound and its respective cation [36], were used to quantify electrophilicity at particular atomic sites of the test compounds. Based on the rationale underlying this work, we considered only Table 2).…”

Comparison of the mechanism of deamination of 5,6-dihydro-5-methylcytosine with other cytosine derivatives

“…These include the local electrophilicity index [48] x ? (r) which is the product of the global electrophilicity index x and the Fukui function [49][50][51] f ? (r); the excess electrophilicity [52] Dx(r) defined as the product of the dual descriptor [53][54][55][56] Df(r) and the global electrophilicity index x and finally another local reactivity index s ð2Þ ðrÞ ¼ Df ðrÞ g 2 derived from the dual descriptor within the grand canonical ensemble [57] (GCDD).…”

Experimental and computational investigations of corrosion and corrosion inhibition of iron in acid solutions

“…The binding energy of the inhibitor molecule is the negative value of the interaction energy [22], namely:…”