Models of solvent

Cativela C., Garcia J. 1., Mayoral J. A., Salvatella L. Modeling of Solvent Effects on the Diels-Alder Reaction Chem. Soc. Rev. 1996 25 209 218... 

Utesch RC, Weir FW, Bruckner JV. 1981. Development of an animal model of solvent abuse for use in evaluation of extreme trichloroethylene inhalation. Toxicology 19 169-182. 

Shang, H. S., and T. Head-Gordon. 1994. Stabilization of Helices in Glycine and Alanine Dipeptides in a Reaction Field Model of Solvent. J. Am. Chem. Soc. 116, 1528-1532. 

Local density functional theory may be introduced within the RF model of solvent effects thorugh the induced electron density. The basic quantity for such a development is the linear density response function [39] ... 

However, the most promising aspect of the DFT-RF model of solvent effects presented here is represented by Eq (102). This expression, derived... 

Coming back to solvent reorganization, the reduction of aromatic hydrocarbons in an aprotic solvent such as DMF provides a series of data that may be used for testing the Marcus-Hush model of solvent reorganization13,61-63... 

Both the electronic couphng matrix element and the outer-sphere component of the nuclear reorientation parameter are thought to vary with donor-acceptor separation and orientation [29, 49]. It has been shown in studies of Os and Ru-ammines bridged by polyproline spacers that the distance dependence of X can be greater than that of [50]. Dielectric continuum models of solvent reorganization predict that Xg will increase with... 

Given that interfacial solvation affects chemical transport/ surface reactivity and electron transfer/ and macromolecular self-assembly/ predictive models of solvent-solute interactions near surfaces will afford researchers deeper insights into a host of phenomena in biology, physics, and engineering. Research in this area should aid efforts to develop a general, experimentally tested, and quantitative understanding of solution-phase surface chemistry. 

Multiparametric models of solvent effects are the IMF and the Kamlet-Taft-Abraham equations. 

Analysis of G t) provides insight into the solvent motions that are most important in SD and also provides a basis for constructing approximations to C(t) in terms of simplified models of solvent dynamics. The two approaches that have... 

There are similar problems and methodologies in the modeling of solvent-solute interactions. In the area of solvent interactions (see also Sections 3.4 and 4) the combination of QM- or MM-based methods with MD has been used successfully in the computational modeling and rather accurate predictions of the ligand-assisted distribution of metal ions between aqueous and organic liquid phases.149,150... 

Since its introduction the Kamlet-Taft it scale has been applied to a large number of diverse liquid solvents ( 5). Several studies have shown that the it solvent scale is consistent with other popular measures of solvent strength (6J. It has also been shown that there are good correlations between the empirical measurements of the Kamlet and Taft scale and several theoretical models of solvent behavior (J). Use of the solutes chosen by Kamlet and... 

By introducing -dependent susceptibilities one can, at a phenomenological level, imitate the molecular structure of solvent around the solute with any desired degree of accuracy. Invoking isotropic and uniform approximations such as Equations (1.138) or (1.140) constrains the ability of such an approach to a certain degree. In any case, this is an essential extension of structureless local models of solvent. 

From its inception, the combined Quantum Mechanics/Molecular Mechanics (QM/MM) method [1-3] has played an important roll in the explicit modeling of solvent [4], Whereas Molecular Mechanics (MM) methods on their own are generally only able to describe the effect of solvent on classical properties, QM/MM methods allow one to examine the effect of the solvent on solute properties that require a quantum mechanical (QM) description. In most cases, the solute, sometimes together with a few solvent molecules, is treated at the QM level of theory. The solvent molecules, except for those included in the QM region, are then treated with an MM force field. The resulting potential can be explored using Monte Carlo (MC) or Molecular Dynamics (MD) simulations. Besides the modeling of solvent, QM/MM methods have been particularly successful in the study of biochemical systems [5] and catalysis [6],... 

In this contribution we will first outline the formalism of the ONIOM method. Although ONIOM has not yet been applied extensively to problems in the solvated phase, we will show how ONIOM has the potential to become a very valuable tool in both the explicit and implicit modeling of solvent effects. For the implicit modeling of solvent, we developed the ONIOM-PCM method, which combines ONIOM with the Polarizable Continuum Method (PCM). We will conclude with a case study on the vertical electronic transition to the it state in formamide, modeled with several explicit solvent molecules. 

The third chapter focuses on the modelization of solvent effects on ground state chemical reactivity and excited state reactive and non-reactive processes. 

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