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
On the dynamics of electrochemical ion-transfer reactions
O. Pecina,Wolfgang Schmickler +1 more
TL;DR: In this paper, a model of an electrochemical ion-transfer reaction was investigated by molecular dynamics simulations, and the resulting transmission coefficient, which measures the deviation of the rate from the predictions of the transition state theory was in good agreement with the Grote-Hynes theory.
Journal ArticleDOI
Generalized Langevin equation with a nonlinear potential of mean force and nonlinear memory friction from a hybrid projection scheme
TL;DR: In this paper , a hybrid projection scheme that combines linear Mori projection and conditional Zwanzig projection techniques was introduced to derive a generalized Langevin equation (GLE) for a general interacting many-body system.
Journal ArticleDOI
On the relation between Marcus theory and ultrafast spectroscopy of solvation kinetics
TL;DR: In this paper, the authors provided a new perspective of ultrafast solvent exchange mechanism around ions measurable by two-dimensional infrared (2DIR) spectroscopy, and computed ion-bound to solvent-bound transition rate for a BF 4 - -water system.
Journal ArticleDOI
Why are some Enzymes Dimers? Flexibility and Catalysis in Thermotoga Maritima Dihydrofolate Reductase.
TL;DR: Using QM/MM potentials, it is shown that the reduced catalytic efficiency of TmDHFR is most likely due to differences in the amino acid sequence that stabilize the M20 loop in an open conformation, which prevents the formation of some interactions in the transition state and increases the number of water molecules in the active site.
Journal ArticleDOI
Solvent Effect on Rotational Motion of Perchlorate Ion
Haruko Hosoi and,Yuichi Masuda +1 more
TL;DR: In this paper, the rotational relaxation times of perchlorate ion, τ2r, in 15 solvents and at various temperatures were determined from the measurements of the 17O NMR spin−lattice relaxation times.
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.