Article

Proton Transfer Studied Using a Combined Ab Initio Reactive Potential Energy Surface with Quantum Path Integral Methodology.

Center for Biophysical Modeling & Simulations and Department of Chemistry, University of Utah, Salt Lake City, Utah, 84112.
Journal of Chemical Theory and Computation (impact factor: 5.22). 09/2010; 6(9):2566-2580. DOI:10.1021/ct900579k pp.2566-2580
Source: PubMed

ABSTRACT The rates of intramolecular proton transfer are calculated on a full-dimensional reactive electronic potential energy surface that incorporates high level ab initio calculations along the reaction path and by using classical Transition State theory, Path-Integral Quantum Transition State Theory, and the Quantum Instanton approach. The specific example problem studied is malonaldehyde. Estimates of the kinetic isotope effect using the latter two methods are found to be in reasonable agreement with each other. Improvements and extensions of this practical, yet chemically accurate framework for the calculations of quantized, reactive dynamics are also discussed.

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Keywords

chemically accurate framework
 
classical Transition State theory
 
full-dimensional reactive electronic potential energy surface
 
intramolecular proton transfer
 
kinetic isotope effect
 
level ab initio calculations
 
Path-Integral Quantum Transition State Theory
 
Quantum Instanton approach
 
reactive dynamics
 
two methods