Results 171 to 180 of about 5,516,918 (194)

On non-negativity of Fukui function indices. II

The Journal of Chemical Physics, 2000
In this article we have tried to critically analyze the factors which cause the condensed Fukui function (FF) indices [f(r)] to attain a negative value in some cases. The evaluation of condensed FF indices needs finite-difference approximation to the electronic charge densities, and the finite-difference approximation needs partitioning of the ...
Ram Kinkar Roy, Kimihiko Hirao, Sourav Pal   +2 more
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A naïve geometrical perspective of Fukui functions: definition of Fukui function skew symmetric matrices described on density function sets

Journal of Mathematical Chemistry, 2012
Recent description on density function (DF) sets of origin shifts is used in the present work to describe in a simple way Fukui functions. The present paper discusses first the possibilities and nuances of the origin shift in sets of three DF, formed by cation, neutral and anion functions; then uses quantum similarity techniques to analyze the ...
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On the quality of the hardness kernel and the Fukui function to evaluate the global hardness

Journal of Computational Chemistry, 2006
AbstractAn approximated hardness kernel, which includes the second derivative with respect to the density of the kinetic energy, the electron–electron coulomb repulsion, and the exchange density functionals, has been tested for the calculation of the global hardness.
Miquel Torrent-Sucarrat, Pedro Salvador, Paul Geerlings, Miquel Solà   +3 more
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A direct evaluation of regional Fukui functions in molecules

Chemical Physics Letters, 1999
Abstract A simple formalism to obtain regional Fukui functions is presented. The model is based on an exact relationship between this local reactivity descriptor and the frontier molecular orbitals. Within this approach, it becomes possible to define an orbital Fukui function that directly yields the condensed-to-atom quantity.
Renato R. Contreras, Patricio Fuentealba, Marcelo Galván, Patricia Pérez   +3 more
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Condensed Fukui function: dependency on atomic charges

Molecular Physics, 1997
The condensed Fukui functions have been calculated using the Mulliken population analysis (MPA) and natural population analysis (NPA) schemes for the molecules BH2F, BH2Cl and trans and cis forms of the FC(O)OF and nitrosoethylene molecules and another isomer of nitrosoethylene, oxazete. The changes in the relative reactive sites of these molecules due
S. ARULMOZHIRAJA, P. KOLANDAIVEL
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Calculation of molecular electrostatic potentials and Fukui functions using density functional methods

Chemical Physics Letters, 1996
Abstract The performance of different density functional methods in the calculation of molecular electrostatic potentials and Fukui functions, i.e. two reactivity indices based on the electron density, is investigated. It turns out, as a whole, that the exact exchange functionals B3LYP and B3PW91 yield results close to accurate electron correlation ...
De Proft, Frank, Martin, Jan M.l., Geerlings, Paul   +2 more
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The nuclear Fukui function and Berlin’s binding function in density functional theory

The Journal of Chemical Physics, 1996
The recently introduced nuclear Fukui function φα is formally identified as a reactivity index of the density functional theory (according to the postulated criterion of |dμ|) and is shown to constitute the conformational contribution to a change in the molecular electronic chemical potential μ, through the relation dμ|N=∫ f(r)dν(r)dr=−∑αφαdRga, with ...
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Fukui Function

2009
Paul Ayers, Weitao Yang, Libero Bartolotti   +2 more
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THE NUCLEAR FUKUI FUNCTION

2002
Geerlings, Paul, De Proft, Frank, Balawender, Robert   +2 more
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Calculation of Fukui Function Without Differentiation to the Number of Electrons. Part III: Local Fukui Function and Dual Descriptor

2008
Calculation of Fukui Function Without Differentiation to the Number of Electrons.
Fievez, Tim, Sablon, Nick, De Proft, Frank, Ayers, P.w., Geerlings, Paul   +4 more
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