Results 261 to 270 of about 5,947,585 (288)

Empirical evaluation of chemical hardness

Chemical Physics Letters, 1987
Abstract Two possible measures of hardness are proposed. An average chemical hardness is calculated separately for acidic and basic reactions of atoms. Differential hardnesses are derived from atomic radii.
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On electronegativity and chemical hardness relationships with aromaticity

Journal of Mathematical Chemistry, 2009
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Tarko, Laszlo, Putz, Mihai V.
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Hard Science = Hard Evidence: Forensic Chemistry and Chemical Detectives

2009
Someone killed the mayor of Chatsberg using a makeshift pipe bomb in Kid Glove Killer (1942). It was connected with a wire to the electrical system of the mayor’s automobile and exploded when he turned the ignition key. The two members of the Chatsberg police forensic team, supervisor Gordon McKay (Van Heflin) and his assistant Jane “Mitchell” Mitchell
Mark A. Griep, Marjorie L. Mikasen
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Chemical hardness — A historical introduction

2006
A brief account is given of the origin and early development of the idea of hardness, introduced to chemistry as hard and soft Lewis acids and bases. There is also a discussion of the merging of this early view of hardness with the modern definition, based on density functional theory.
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Hybridization effect on chemical potential and hardness — a quantum chemical study

Chemical Physics Letters, 1996
Abstract The hybridization effect on two important quantities, chemical hardness abd chemical potential, has been studied by HF-SCF theory using a 6-31G basis set. The maximum hardness principle has been tested for CC and CH symmetric stretching with positive and negative mean amplitudes of vibration.
P. Kolandaivel, S. Arulmozhiraja, R. Bhuvaneswari   +2 more
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Perturbed reactivity descriptors: the chemical hardness

Theoretical Chemistry Accounts, 2017
A simple framework to study the effects of (small) external perturbations on conceptual density functional theory descriptors is discussed. Based on this, the general expressions recently presented for the perturbed chemical potential are revisited.
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Density functional theory of chemical hardness

2006
The ideas of chemical hardness and chemical softness are reviewed, with special emphasis on the research work done on these concepts at the University of North Carolina at Chapel Hill.
Pratim K. Chattaraj, Robert G. Parr
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Chemicals hit hard in Olin reorganization

Chemical & Engineering News Archive, 1991
Chemical operations will be hit hard in a reorganization announced last week by Olin Corp. in an attempt to increase its cash flow, lower its costs, and reduce its debt. Based on plans announced by the Stamford, Conn.-based company, its chemicals operations will bear the brunt of cuts through sales of businesses and staff reductions.
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Chemical hardness and bond dissociation energies

Journal of the American Chemical Society, 1988
An empirical method is proposed to rank order Lewis acids and bases in terms of their local hardness, {tilde {eta}}, at their reaction sites. The method uses bond energy differences between two acids (or bases) of different chemical hardness. The assumption is made that in an exchange reaction, A:B' + A':B = A:B + A':B', the most stable pair will match
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Electronegativity and hardness of chemical groups

The Journal of Physical Chemistry, 1993
Ludwik Komorowski, Jozef Lipinski, Maciej J. Pyka   +2 more
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