Results 251 to 260 of about 5,947,585 (288)

Orbital Interactions and Chemical Hardness

The Journal of Physical Chemistry, 1994
Electron delocalization between molecules in chemical reactions is represented compactly in terms of the pairs of localized interacting orbitals. These interacting orbitals are illustrated to be reproduced approximately by projecting on to the occupied and unoccupied MO subspaces of an isolated reactant molecule a reference orbital function that has ...
Hiroshi Fujimoto, Shinichi Satoh
openaire   +1 more source

Substituent effects on chemical hardness

International Journal of Quantum Chemistry, 1994
AbstractIt is shown that for a number of molecules there exists a Hammett‐like equation for the chemical hardness or the HOMO‐LUMO energy gap. Substituent effects can be factored out of the molecular hardness. Preliminary results show that a hardness substituent constant, similar to the Hammett σ‐constant, can be defined and determined for each ...
John Kneisler, Zhongxiang Zhou
openaire   +1 more source

Chemical hardness and the electronic chemical potential

Inorganica Chimica Acta, 1992
The properties of the electronic chemical potential, μ and the chemical hardness, η, are summarized. Rules-of-thumb are given for predicting the changes in μ and η when small subsystems are combined to form larger systems. In general, the hardness increases when the energy decreases.
openaire   +1 more source

The electronic chemical potential and chemical hardness

Journal of Molecular Structure: THEOCHEM, 1992
Abstract Two quantities, derived from density functional theory, that help define any chemical system are the electronic chemical potential and the chemical hardness. Some of the properties and applications of these fundamental quantities are described.
openaire   +1 more source

On Hardness and Electronegativity Equalization in Chemical Reactivity Theory

Journal of Statistical Physics, 2006
zbMATH Open Web Interface contents unavailable due to conflicting licenses.
Cohen, Morrel H., Wasserman, Adam
openaire   +1 more source

Chemical potentials of hard polyatomic solutes in hard sphere fluids

The Journal of Chemical Physics, 1997
Monte Carlo measurements of the chemical potential of hard polyatomics of different conformations dissolved in hard sphere fluids are reported. These are compared with analytical expressions derived from the hard fluid model, performed as a function of solute size and solvent density.
Argyroula Stamatopoulou, Dor Ben-Amotz
openaire   +1 more source

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 ...
openaire   +1 more source

Chemical potential, hardness, hardness and softness kernel and local hardness in the isomorphic ensemble of density functional theory

The Journal of Chemical Physics, 1997
New relations among reactivity descriptors are provided within the recently introduced modified isomorphic ensemble of density functional theory. In addition, expressions for the softness and hardness kernel are derived in the canonical, grand canonical, isomorphic, and grand isomorphic ensemble. There results a new definition for the local hardness, η(
De Proft, Frank, Liu, S., Parr, R.g.
openaire   +2 more sources

Electronegativity and hardness in the chemical approximation

Chemical Physics, 1987
Abstract The chemical electronegativity of an atom (Mulliken definition) has been identified with the average value of χ, the electronegativity function given by the rigorous density functional theory. An appropriate definition of hardness is developed, and a scale of hardness for bonded atoms is proposed.
openaire   +1 more source

Electronegativity and chemical hardness of organoelement groups

Applied Organometallic Chemistry, 2001
The experimental approaches to estimation of comparative electronegativity and chemical hardness of organometallic groups have been proposed. Qualitative data on the electronegativity of L n M groups were obtained from F NMR study of model systems 4-FC 6 H 4 QML n (Q = C≡C, N(R), O, C(O)O, S), (4-FC 6 H 4 ) 3 SnML n and (4-FC 6 H 4 ) 3 SnQML n (Q =
Alexander S. Peregudov, Dmitrii N. Kravtsov   +1 more
openaire   +1 more source