Condensed phases energy

It is well known that in condensed phases energy transfer can occur between rotational and vibrational states. Indeed, molecular rotation does not actually occur in liquids rotational states turn into vibrational states because of an increase in collisions. 

With reference to Figs. 3.9 and 3.10, the energy and the species equations are condensed-phase energy equation ... 

The highly excited states of molecules produced by high-energy radiation that arc chemically important are mainly the ionic states because of the rapidity of internal conversion processes. Primary excitation is relatively unimportant while secondary excitation is quite common. In the condensed phases energy dissipation is very rapid because of colli-sional deactivation, the cage effect, and excitation energy transfer processes all of which act to negate the chemical effects of secondary excitation,... 

The condensed phase energy equation, being decoupled from the species... 

Correlation of free-ion and condensed-phase energy level structures... 

This section discusses how spectroscopy, molecular beam scattering, pressure virial coeflScients, measurements on transport phenomena and even condensed phase data can help detemiine a potential energy surface. 

Because of the general difficulty encountered in generating reliable potentials energy surfaces and estimating reasonable friction kernels, it still remains an open question whether by analysis of experimental rate constants one can decide whether non-Markovian bath effects or other influences cause a particular solvent or pressure dependence of reaction rate coefficients in condensed phase. From that point of view, a purely... 

Leitner D M 1999 influence of quantum energy flow and localization on molecular isomerization in gas and condensed phases Int. J. Quant. Chem. 75 523-31... 

A3.8.2 THE ACTIVATION FREE ENERGY AND CONDENSED PHASE EFFECTS... 

Wang Y A and Carter E A 2000 Orbital-free kinetic-energy density functional theory Theoretical Methods in Condensed Phase Chemistry (Progress in Theoretical Chemistry and Physics Series) ed S D Schwartz (Boston Kluwer) pp 117-84... 

The tenn represents an externally applied potential field or the effects of the container walls it is usually dropped for fiilly periodic simulations of bulk systems. Also, it is usual to neglect v - and higher tenns (which m reality might be of order 10% of the total energy in condensed phases) and concentrate on For brevity henceforth we will just call this v(r). There is an extensive literature on the way these potentials are detennined experimentally, or modelled... 

Much of chemistry occurs in the condensed phase solution phase ET reactions have been a major focus for theory and experiment for the last 50 years. Experiments, and quantitative theories, have probed how reaction-free energy, solvent polarity, donor-acceptor distance, bridging stmctures, solvent relaxation, and vibronic coupling influence ET kinetics. Important connections have also been drawn between optical charge transfer transitions and thennal ET. 

Chemical reaction dynamics is an attempt to understand chemical reactions at tire level of individual quantum states. Much work has been done on isolated molecules in molecular beams, but it is unlikely tliat tliis infonnation can be used to understand condensed phase chemistry at tire same level [8]. In a batli, tire reacting solute s potential energy surface is altered by botli dynamic and static effects. The static effect is characterized by a potential of mean force. The dynamical effects are characterized by tire force-correlation fimction or tire frequency-dependent friction [8]. 

Bash, P.A., Field, M.J.,Karplus, M. Free energy perturbation method for chemical reactions in the condensed phase A dynamical approach baaed on a combined quantum and molecular dynamics potential. J. Am. Chem. Soc. 109 (1987) 8092-8094. 

This technique for finding a weighted average is used for ideal gas properties and quantum mechanical systems with quantized energy levels. It is not a convenient way to design computer simulations for real gas or condensed-phase... 

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