AbInitio Calculation of Rate Constants for Molecule-Surface Reactions with Chemical Accuracy

The abinitio prediction of reaction rate constants for systems with hundreds of atoms with an accuracy that is comparable to experiment is a challenge for computational quantum chemistry. We present a divide-and-conquer strategy that departs from the potential energy surfaces obtained by standard de...

Full description

Saved in:
Bibliographic Details
Published in:Angewandte Chemie International Edition 2016-04, Vol.55 (17), p.5235
Main Authors: Piccini, GiovanniMaria, Alessio, Maristella, Sauer, Joachim
Format: Article
Language:English
Subjects:
Accuracy
Alkenes
Anharmonicity
Catalysis
Chemical reactions
Chemistry
Computer applications
Constants
Density
Density functional theory
Dispersion
Energy
Enthalpy
Functional anatomy
Harmonic functions
Kinetics
Mathematical analysis
Methylation
Potential energy
Quantum chemistry
Rate constants
Surface reactions
Temperature effects
Zeolites
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:The abinitio prediction of reaction rate constants for systems with hundreds of atoms with an accuracy that is comparable to experiment is a challenge for computational quantum chemistry. We present a divide-and-conquer strategy that departs from the potential energy surfaces obtained by standard density functional theory with inclusion of dispersion. The energies of the reactant and transition structures are refined by wavefunction-type calculations for the reaction site. Thermal effects and entropies are calculated from vibrational partition functions, and the anharmonic frequencies are calculated separately for each vibrational mode. This method is applied to a key reaction of an industrially relevant catalytic process, the methylation of small alkenes over zeolites. The calculated reaction rate constants (free energies), pre-exponential factors (entropies), and enthalpy barriers show that our computational strategy yields results that agree with experiment within chemical accuracy limits (less than one order of magnitude).
ISSN:1433-7851
1521-3773
DOI:10.1002/anie.201601534