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The different mechanisms which trigger electron transfer has been studied along with an explanation of electron hopping under an experimental situation. The research seeks to find out possible causes of electron hopping in supramolecular structures and to derive spatio temporal diffusion-migration equations incorporating intermolecular interaction energy effects. Spin exchange dynamics is used in studying the transport phenomena for the ion pairing mechanism.

The coupling of electroactive oxidized and reduced species as well as electroactive ion-electroinactive counterion coupling inside the redox polymer on steady state current-potential responses has been studied. The Ising model is used in deriving the diffusion-migration which is then utilized in analyzing the steady-state current potential responses and intermolecular interaction. Results show that the rate of charge transport is dependent on association of electroactive species with inactive counterions along with interaction between electron transfer active species.

A study to develop expressions for electron field assisted electron jumping into polymer matrices connected to electrode surfaces is made using principles of irreversible thermodynamics integrated with activity coefficients and interparticle interactions. The transport dynamics equation developed is a mixture of the Dahms-Ruff diffusion and the Levich migration terms and the equation for electron flux is according to a second-order law in species concentrations. Characteristics of Self and tracer diffusion coeffients are included within the concept of charge transport in supramolecular structures.

A microscopic statistical mechanical theory of solvation dynamics is presented. The theory is capable of reproducing the characteristic multiphasic behavior of the solvation correlation function typically observed in the time-resolved spectroscopic studies. The fast initial decay of the solvation correlation function is modeled on the basis of a short-time expansion, while the slowly varying long-time tail is computed within the mode-coupling theory formalism. Comparison with simulation for nonpolar solvation shows that the present theory provides a very substantial improvement over the commonly used time-dependent density functional and surrogate Hamiltonian treatments of the slow component of solvation dynamics. In addition, the range of applicability of the results obtained in this study is much wider compared to the other theories. The mode-coupling theory of solvation is tested for model nonpolar systems consisting of both a neat fluid and a system, where the chromophore size is significantly different from that of the solvent particles. A systematic study of the dependence of the solvation time scales on the size of the chromophore is carried out. [ABSTRACT FROM AUTHOR]

A fully microscopic molecular hydrodynamic theory for the third-order Raman spectrum of an atomic liquid (Xe) is presented. The spectrum is obtained from a mode-coupling theory by projecting the dynamics onto bilinear pairs of fluctuating density variables. For the densities and temperatures studied, semiquantitative agreement is obtained in comparison with molecular dynamics simulation on all time scales. The theory is contrasted with previous molecular hydrodynamic theories of depolarized light scattering spectra. Extensions of the approach outlined here to both classical molecular and quantum liquids are presented. The theory presented here represents the first microscopic solvation theory which quantitatively captures both the inertial and long-time dynamics as well as the crossover between these regimes. © 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Building upon the framework of the preceding paper, a molecular hydrodynamic theory of the fifth-order (two-dimensional) nonresonant Raman spectrum in a simple liquid is presented. A multi-time mode-coupling-like theory is developed and compared with recent computer simulations for liquid Xe. The theory is able to provide a microscopic rationale for the absence of an echo in this system. Experimental predictions for the temperature and density dependence of the signal are presented. Comparison is made with the instantaneous-normal-mode theory. The limitations of the present approach are discussed.© 2002 American Institute of Physics. [ABSTRACT FROM AUTHOR]

This research presents a generalized theory of barrierless isomation reactions in viscous liquids. The theory includes the bimodal frictional response of the solvent.

The properties and control of the charge propagation in polymer-modified electrodes are examined within an irreversible thermodynamics framework. The control of the mobile electroinactive ions on the charge transport is dependent on the strength of the ions pairs it forms with electroactive ions. The strength of the ion pairs is inversely related to the strength of the charge transport. It is shown that the coupling of the electron hopping of localized sites and electroinactive counterion is determined by the redox active and electroinactive counterion diffusivities.

A novel algorithm for the connecting of fragment molecules is presented and validated for a number of test systems. Within the CONFIRM (Connecting Fragments Found in Receptor Molecules) approach a pre-prepared library of bridges is searched to extract those which match a search criterion derived from known experimental or computational binding information about fragment molecules within a target binding site. The resulting bridge ‘hits’ are then connected, in an automated fashion, to the fragments and docked into the target receptor. Docking poses are assessed in terms of root-mean-squared deviation from the known positions of the fragment molecules, as well as docking score should known inhibitors be available. The creation of the bridge library, the full details and novelty of the CONFIRM algorithm, and the general applicability of this approach within the field of fragment-based de novo drug design are discussed. [ABSTRACT FROM AUTHOR]

Recommends the use of riddles in teaching entry-level chemistry classes. Examples of riddles on chemical elements and their compounds; Effectiveness of the method in encouraging students to participate in class discussion and increase their learning.