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Data Formats for Elementary Gas Phase Kinetics: Part 2. Unique Representations of Reactions



Donald R. Burgess Jr., Jeffrey A. Manion, Carrigan J. Hayes


A method of extending the IUPAC International Chemical Identifier (InChI) to describe and identify elementary reactions in a standard computer readable notation is proposed. Denoted InChI-ER, the method is based on the existing InChI formalism, with certain refinements for the better identification of molecular entities as proposed in the preceding article in this journal. Using this base notation, an identifier for elementary reactions on a molecular level is created by adding additional layers in a conceptually similar and extensible manner. Two of the layers describe the atoms involved in the transition-state and the connectivity changes that occur during the reaction. Additional layers classify the reactions on the basis of the connectivity changes, providing chemical information useful in organizing and searching kinetic data sets found in databases or used in detailed kinetic modeling. Important aspects of the method are that the proposed layers are optional, that they do not interfere with existing InChI specifications, and that they retain extensibility should further refinements be desired in the future. Its utility for organizing data is illustrated by implementation for a representative combustion mechanism provided in supplementary material.
International Journal of Chemical Kinetics


IUPAC, InChI, cheminformatics, molecular structure, electronic states, molecular conformations, chemical kinetics, transition states, reaction class, chemical species


Burgess, D. , Manion, J. and Hayes, C. (2015), Data Formats for Elementary Gas Phase Kinetics: Part 2. Unique Representations of Reactions, International Journal of Chemical Kinetics, [online], (Accessed May 26, 2024)


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Created March 25, 2015, Updated November 10, 2018