Liquid molecular comparison

FIGURE 10.1 A molecular comparison of gases, liquids, and solids, (a) In gases, the particles feel little attraction for one another and are free to move about randomly, (b) In liquids, the particles are held close together by attractive forces but are free to move over one another, (c) In solids, the particles are rigidly held in an ordered arrangement. 

Sprik M, Hutter J, Parrinello M (1996) Ab initio molecular dynamics simulation of liquid water comparison of three gradient-corrected density functionals, J Chem Phys 105 1142-1152... 

Sprik M, J Hutter and M Parrinello 1996. Ab Initio Molecular E>)mainics Simulation of Liquid Water. Comparison of Three Gradient-corrected Density Functionals Journal of Chemical Physics 105 1142-1152. 

The inability of ionic liquids to interact strongly with neutral nucleophilic species has been considered recently to be the main factor determining the high rate of rearrangement of the Z-phenylhydrazone of 3-benzoyl-5-phenyl-l,2,4-oxadiazole in ionic liquids in comparison to molecular solvents (Scheme 5.1-13) [42]. 

SECTION 11.1 A Molecular Comparison of Gases, Liquids, and Solids 427... 

MOLECULAR COMPARISONS OF GASES, LIQUIDS, AND SOLIDS (section 11.1)... 

Surfactants play an important role in the formation and stability of foams. Investigators have determined foam stability by measuring the half-life (e.g. t 2) the foam. Half-life is the time required to reduce foam voLume to half of its initial value. It has been demonstrated that the foam stability (i.e.half-life) decreased with increasing temperature, whereas the foaminess of the surfactant solution increased with temperature. It is likely that these properties of foam depend on the molecular structure and concentration of the surfactant at the gas/liquid interface. Comparison of the results of static foam stability with that of the dynamic behavior of foam in porous media revealed that the foam stability is not required for efficient fluid displacement or a decrease in the effective air mc >ility in a porous medium. Moreover, the ability of the surfactants to produce in-situ foam was one of the important factors in the displacement of the fluid in a porous medium. 

A MOLECULAR COMPARISON OF GASES, LIQUIDS, AND SOLIDS We begin with a comparison of solids, liquids, and gases from a molecular perspective. This comparison reveals the important roles that temperature and intermolecular forces play in determining the physical state of a substance. 

M. Sprik, J. Hutter, and M. Parrinello,/. Chem. Phys., 105,1142 (1996). Ab Initio Molecular Dynamics Simulation of Liquid Water Comparison of Three Gradient-Corrected Density Functions. 

We are far here from aiming to advise anybody about future research projects. The only message that we would like to communicate is that a chemical reaction is not necessarily surprising or important because it somehow works as well in an ionic liquid. One should look for those applications in which the specific properties of the ionic liquids may allow one to achieve something special that has not been possible in traditional solvents. If the reaction can be performed better (whatever you may mean by that) in another solvent, then use that solvent. In order to be able to make that judgement, it is imperative that we all include comparisons with molecular solvents in our studies, and not only those that we loiow are bad, but those that are the best alternatives. 

Figure 5.62 Product-ion MS-MS spectra of the molecular ions from 8-hydroxy-2 -deoxyguanosine, obtained by (a) positive, and (b) negative ionization. Reprinted by permission of Elsevier Science from Comparison of negative- and positive-ion electrospray tandem mass spectrometry for the liquid chromatography-tandem mass spectrometry analysis of oxidized deoxynucleosides , by Hua, Y., Wainhaus, S. B., Yang, Y., Shen, L., Xiong, Y., Xu, X., Zhang, F. Bolton, J. L. and van Breemen, R. B., Journal of the American Society for Mass Spectrometry, Vol. 12, pp. 80-87, Copyright 2000 by the American Society for Mass Spectrometry.

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