Reactivity molecular

For two-equivalent couplers where the conversion of the leuco dye to image dye is rapid, the experimentally observed second-order rate constant, k, can be equated with kj, the rate of nucleophilic attack of coupler anion on oxidized developer. Thus when the pH of the process is specified, two parameters, piC and k, can be convenientiy used to characterize the molecular reactivity of a large variety of photographically weU-behaved couplers (40,54). 

One of the fundamental objectives of chemistry is the prediction and rationalization of molecular reactivity. In principle, this involves the construction of an... 

We can distinguish between static theories, which in essence give a description of the electron density, and dynamic theories, where an attempt is marie to measure the response of a molecule to (e.g.) an approaching N02" " ion. In recent years, the electrostatic potential has been used to give a simple representation of the more important features of molecular reactivity. It can be calculated quite easily at points in space ... 

Weinstein, H., R. Osman, J. P. Green, and S. Topiol. 1981a. Electrostatic Potentials as Descriptors of Molecular Reactivity The Basis for Some Successful Predictions of Biological Activity. In Chemical Applications of Atomic and Molecular Electrostatic Potentials. P. Politzer and D. G. Truhlar, Eds. Plenum Press, New York. 

Scheme 2.28 Complementary molecular reactivity and molecular recognition for library purification.

This short analysis of the molecular reactivity of [Mo(CO)6] shows that one or more CO ligands can be displaced quite easily, and that various oxidation states can be reached. Though such chemical behavior carmot be directly applied to the reactivity of surface functionalities with [Mo(CO)6], it might provide useful suggestions about possible similarities. 

In the absence of defects, the reactivity of organic solids is mainly determined by molecular packing. Reactions in which the crystal structure holds sway over intrinsic molecular reactivity are said to be topochemically controlled (Thomas, 1974). A classic example of a topochemically controlled organic reaction in the solid state is the photodimerization of rrans-cinnamic acids studied by Schmidt et al. (see Ginsburg,... 

Molecular Reactivity and Chemical Bonds Main Aspects... 

Parlow J. J. Flynn, D. L. Solution-Phase Parallel Synthesis of a Benzoxaz-inone Library Using Complementary Molecular Reactivity and Molecular Recognition (CMR/R) Purification Technology, Tetrahedron 1998,54,4013. 

When potential surfaces are available, quasiclassical trajectory calculations (first introduced by Karplus, et al.496) become possible. Such calculations are the theorist s analogue of experiments and have been quite successful in simulating molecular reactive collisions.497 Opacity functions, excitation functions, and thermally averaged rate coefficients may be computed using such treatments. Since initial conditions may be varied in these calculations, state-to-state cross sections can be obtained, and problems such as vibrational specificity in the energy release of an exoergic reaction and vibrational selectivity in the energy requirement of an endo-... 

Supramolecular reactivity and catalysis thus involve two main steps binding, which selects the substrate, and transformation of the bound species into products within the supermolecule formed. Both steps take part in the molecular recognition of the productive substrate and require the correct molecular information in the reactive receptor. Compared to molecular reactivity, a binding step is involved that precedes the reaction itself. Catalysis additionally comprises a third step, the release of the substrate. 

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