The Library
Sampling reactive pathways with random walks in chemical space : applications to molecular dissociation and catalysis
Tools
Habershon, Scott (2015) Sampling reactive pathways with random walks in chemical space : applications to molecular dissociation and catalysis. The Journal of Chemical Physics, 143 (9). 094106. doi:10.1063/1.4929992 ISSN 0021-9606.
PDF
WRAP_1.4929992.pdf - Published Version - Requires a PDF viewer. Download (2503Kb) |
Official URL: http://dx.doi.org/10.1063/1.4929992
Abstract
Automatically generating chemical reaction pathways is a significant computational challenge, particularly in the case where a given chemical system can exhibit multiple reactants and products, as well as multiple pathways connecting these. Here, we outline a computational approach to allow automated sampling of chemical reaction pathways, including sampling of different chemical species at the reaction end-points. The key features of this scheme are (i) introduction of a Hamiltonian which describes a reaction “string” connecting reactant and products, (ii) definition of reactant and product species as chemical connectivity graphs, and (iii) development of a scheme for updating the chemical graphs associated with the reaction end-points. By performing molecular dynamics sampling of the Hamiltonian describing the complete reaction pathway, we are able to sample multiple different paths in configuration space between given chemical products; by periodically modifying the connectivity graphs describing the chemical identities of the end-points we are also able to sample the allowed chemical space of the system. Overall, this scheme therefore provides a route to automated generation of a “roadmap” describing chemical reactivity. This approach is first applied to model dissociation pathways in formaldehyde, H2CO, as described by a parameterised potential energy surface (PES). A second application to the HCo(CO)3 catalyzed hydroformylation of ethene (oxo process), using density functional tight-binding to model the PES, demonstrates that our graph-based approach is capable of sampling the intermediate paths in the commonly accepted catalytic mechanism, as well as several secondary reactions. Further algorithmic improvements are suggested which will pave the way for treating complex multi-step reaction processes in a more efficient manner.
Item Type: | Journal Article | ||||||||
---|---|---|---|---|---|---|---|---|---|
Subjects: | Q Science > QD Chemistry | ||||||||
Divisions: | Faculty of Science, Engineering and Medicine > Science > Chemistry | ||||||||
Library of Congress Subject Headings (LCSH): | Reactivity (Chemistry), Chemical reaction, Rate of | ||||||||
Journal or Publication Title: | The Journal of Chemical Physics | ||||||||
Publisher: | American Institute of Physics | ||||||||
ISSN: | 0021-9606 | ||||||||
Official Date: | 3 September 2015 | ||||||||
Dates: |
|
||||||||
Volume: | 143 | ||||||||
Number: | 9 | ||||||||
Article Number: | 094106 | ||||||||
DOI: | 10.1063/1.4929992 | ||||||||
Status: | Peer Reviewed | ||||||||
Publication Status: | Published | ||||||||
Access rights to Published version: | Restricted or Subscription Access | ||||||||
Date of first compliant deposit: | 27 January 2016 | ||||||||
Date of first compliant Open Access: | 27 January 2016 | ||||||||
Funder: | University of Warwick |
Request changes or add full text files to a record
Repository staff actions (login required)
View Item |
Downloads
Downloads per month over past year