Journal ArticleDOI
The stable states picture of chemical reactions. II. Rate constants for condensed and gas phase reaction models
Richard F. Grote,James T. Hynes +1 more
TLDR
In this paper, the stable states picture (SSP) was used to derive the time correlation function (tcf) for the rate constant κ for a wide variety of gas and solution phase reaction models.Abstract:
The time correlation function (tcf) formulas for rate constants κ derived via the stable states picture (SSP) of chemical reactions are applied to a wide variety (a–d) of gas and solution phase reactionmodels. (a) For gas phase bimolecular reactions, we show that the flux tcf governing κ corresponds to standard numerical trajectory calculation methods. Alternate formulas for κ are derived which focus on saddle point surfaces, thus increasing computational efficiency. Advantages of the SSP formulas for κ are discussed. (b) For gas phase unimolecular reactions, simple results for κ are found in both the strong and weak coupling collision limits; the often ignored role of product stabilization is exposed for reversible isomerizations. The SSP results correct some standard weak coupling rate constant results by as much as 50%. (c) For barrier crossing reactions in solution, we evaluate κ for a generalized (non‐Markovian) Langevin description of the dynamics. For several realistic models of time dependent friction, κ differs dramatically from the popular Kramers constant friction predictions; this has important implications for the validity of transition state theory. (d) For solutionreactions heavily influenced by spatial diffusion, we show that the SSP isolates short range reaction dynamics of interest and includes important barrier region effects in structural isomerizations often missed in standard descriptions.read more
Citations
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Journal ArticleDOI
Colored non-gaussian noise driven open systems: generalization of Kramers' theory with a unified approach.
TL;DR: The calculated escape rate from a meta stable state in the presence of both colored internal thermal and external nonthermal noises is valid for low noise strength of non-gaussian noise such that an effective gaussian approximation ofnon-GAussian noise wherein the higher order even cumulants of order "4" and higher are neglected.
Journal ArticleDOI
Bimodality of the viscoelastic response of a dense liquid and comparison with the frictional responses at short times
TL;DR: In this article, a detailed study of the time and frequency dependencies of the viscosity has been carried out and compared with those of the friction, based on the mode coupling theory (MCT).
Journal ArticleDOI
Applicability of the Caldeira-Leggett Model to Vibrational Spectroscopy in Solution.
TL;DR: It is shown that the mapping between a molecular system under study and the model cannot be established in a self-consistent way, unless the system part of the potential is taken effectively harmonic.
Journal ArticleDOI
Theoretical investigations of proton and hydrogen atom transfer in the condensed phase
TL;DR: Theoretical studies of the dynamics and kinetics of proton and hydrogen atom transfer processes occupy a special place in the kinetic of chemical reactions as mentioned in this paper, and the transition state theory is often inapplicable to these processes due to substantial quantum effects.
Journal ArticleDOI
Field-resolved measurement of reaction-induced spectral densities by polarizability response spectroscopy.
TL;DR: The experimental design and theoretical description of a novel five-pulse laser spectroscopy is presented with an application to a pyridinium charge transfer complex in acetonitrile and methanol and the solvent-dependent and time-evolving polarizability spectral density (PSD) is readily obtained.
References
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Journal ArticleDOI
Brownian motion in a field of force and the diffusion model of chemical reactions
TL;DR: In this article, a particle which is caught in a potential hole and which, through the shuttling action of Brownian motion, can escape over a potential barrier yields a suitable model for elucidating the applicability of the transition state method for calculating the rate of chemical reactions.
BookDOI
Dynamics of Molecular Collisions
TL;DR: In this paper, the potential energy surfaces and their effect on collision processes are discussed. But the authors focus on the nonadiabatic processes in collision theory and not on the classical trajectories of trajectories.