Results 241 to 250 of about 88,027 (290)

Electronegativity:  Chemical Hardness II

Journal of Physical Chemistry A, 1997
It has been suggested that the absolute hardness of density functional theory be identified with the chemical hardness of Pearson's principle of hard and soft acids and bases.
James L Reed
exaly   +2 more sources

Chemical and physical “hardness”

Materials Research Innovations, 1997
A common theme links chemical, mechanical, and optical hardnesses. It is the gap in the bonding energy spectra of materials. This gap determines molecular stability, and therefore ”chemical hardness”. Chemists call it the LUMO-HOMO gap between anti-bonding and bonding molecular orbitals.
John J Gilman
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Hardness dynamics in a chemical reaction

Chemical Physics Letters, 1994
Temporal evolution of local and global hardness during a chemical reaction modelled as a collision process between a nitrogen atom and a proton has been studied within a quantum fluid density functional framework. Variation of local hardness is similar to that of charge density.
P.K. Chattaraj, S. Nath
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CHEMICAL AND PHYSICAL HARDNESS OF SOLIDS

MRS Proceedings, 2004
ABSTRACTThe concept of chemical hardness was originally developed as a measure of the stability of molecules. Its relationship to physical hardness and to solids is demonstrated here. Also, it is shown that shear moduli, and polarizabilitites, as well as band gaps are related to chemical hardness.
John J. Gilman
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SEMICLASSICAL ELECTRONEGATIVITY AND CHEMICAL HARDNESS

Journal of Theoretical and Computational Chemistry, 2007
The semiclassical path integral approach is undertaken to develop new definitions and atomic scales of electronegativity and chemical hardness. The considered quantum probability amplitude up to the fourth-order expansion provides intrinsic electronegativity and chemical hardness analytical expressions in terms of principal quantum number of the ...
Mihai V Putz
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Change of Hardness and Chemical Potential in Chemical Binding: A Quantitative Model

The Journal of Physical Chemistry, 1994
In this paper we relate the change of chemical hardness and potential with the binding energies as the chemical binding takes place. We use a simple model to demonstrate that the hardness change is not only related to the binding energy of the molecule being formed, but also to the binding energies of the corresponding molecular cations and anions ...
Sourav Pal, Ramkinkar Roy, A. K. Chandra
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Maximum Chemical and Physical Hardness

Journal of Chemical Education, 1999
Density functional theory (DFT) is briefly reviewed, especially concepts such as the electronic chemical potential and the hardness of the electron density function. There is much evidence, and a mathematical proof, that this chemical hardness is a maximum for an equilibrium system.
Ralph G Pearson
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Kaya's composite descriptor and Maximum Composite Hardness Rule for chemical reactions

Journal of the Indian Chemical Society, 2022
Within the framework of Maximum Hardness and Minimum Polarizability Principles and as compatible with Jenkins Volume Based Thermodynamics approach, Kaya and coworkers calculated the lattice energies of inorganic ionic crystals using their eta(M)/V-m(1/3)
Savas Kaya, Nihat Karakus
exaly   +2 more sources

A new equation for calculation of chemical hardness of groups and molecules

Molecular Physics, 2015
Chemical hardness is considered to be a useful theoretical descriptor in many experimental and theoretical studies and this concept has several important applications in chemistry. In this study, an equation for atomic hardness is proposed. Following the
Savas Kaya, Cemal Kaya
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