solvent effects and chemical reactivity (tapia & bertrán)

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solvent effects and chemical reactivity (tapia & bertrán)

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[...]... correlation functions and, in particular, interaction-site model–RISM– by D Chandler and H.C Andersen and later extended for the treatment of polar and ionic systems by Rossky and coworkers Path integral method is currently being employed in this field By and large, we believe that the most important aspects of the theory and practice of solvent effects have been covered in this book and we apologize to... applications, e.g., dynamics and spectroscopy, one must consider the various time scales of the solvation process and the dynamical process under consideration, and the final section of the review discusses these issues 1 O Tapia and J Bertrán (eds.), Solvent Effects and Chemical Reactivity, 1–80 © 1996 Kluwer Academic Publishers Printed in the Netherlands 2 C J CRAMER AND D G TRUHLAR 1 Introduction... means the solvation of localized states and, as a consequence, that the free energy from the solvent point of view is lower than the solvation of the delocalized self-consistent charge distribution In chapter 7, Profs Tapia, Andrés and Stamato give an extended analysis of the quantum mechanics of solvent effects, chemical reactions and their reciprocal effects The stand point is somewhat different from... the concept of quantum resonaces at the interconversion step The theory of solvent effects on chemical reactions is then framed independently of current quantum chemical procedures As the chapter unfolds, an extended overview is included of important work reported on solvent effects and chemical reaction A book on solvent effects today cannot claim completeness The field is growing at a dazzling pace... a solvent, namely the bulk polarization 16 C J CRAMER AND D.G TRUHLAR of the solvent by the mean field of the solute Thus the model admittedly neglects all other physical effects One of these, electron correlation between the solute and the solvent, was mentioned explicitly already This and other physical effects missing in the SCRF method are discussed in more detail in this section As a shorthand... nelectrons and m-nuclei is examined with special emphasis on possible shortcomings of the Born-Oppenheimer framework when it is applied to a chemical interconversion process Time dependent phenomena is highligthed The authors go a step beyond previous wave mechanical treatments of solvent effects by explicitly including a time-dependent approach to solvent dynamics and solute -solvent coupling Solvent. .. continuum models need not be abandoned for treating such effects In fact, continuum models have some significant advantages for such treatments, just as they do for treating bulk electrostatic effects 18 C J CRAMER AND D G TRUHLAR The key to the continuum treatment of first solvation-shell effects is the concept of solvent- accessible surface area, introduced by Lee and Richards [63] and Hermann [64] In a continuum... effects “non-electrostatic” (and abbreviate them N), but a more precise wording would be that used in Section 1, namely and “non-bulktype electrostatic.” Electron correlation between the solute and solvent has an important quantitative effect on the solvation free energy The most important qualitative manifestation of this correlation is the existence of dispersion interactions between solute and solvent. .. may have significant effects, both enthalpic and entropic, on solvent structural properties The dispersion and solvent structural aspects of cavitation are two physical effects not accounted for in the treatment of the previous section, with its assumption of an uncorrelated, homogeneous dielectric medium with dielectric constant equal to the bulk value Certain aspects of the solvent structural changes... approach, and the QM/MM and fully MM methods that treat solvent molecules explicitly, share the disadvantage that they all require efficient techniques for the sampling of phase space For the QM/MM and fully MM approaches, this sampling problem becomes the computational bottleneck When structural and dynamical information about the solvent molecules themselves is not of primary interest, the solute-solvent .

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