Constructing Reaction Mechanisms

There are many other systems, particularly those important in the processing of inorganic materials, that could potentially be modeled with similar success using detailed chemical kinetic modeling. However, in these cases we generally have very few experimentally measured rate parameters and may not even have experimentally determined thermochemical properties (enthalpy of formation, standard entropy, etc.) for many of the important chemical species. While experiments are still the most reliable source for most of the needed data, they are also in many 

Comprehensive Chemical Kinetics, Volume 42, 185-242 Copyright 2007 Elsevier B.V. All rights reserved. ISSN 0069-8040/doi 10.1016/80069-8040(07)42005-2 

The overall process for constructing a detailed reaction mechanism is illustrated schematically in Fig. 1. As shown there, we can envision this process as a sequence of steps in which the primary information flow is from one step to the next, vertically downward in the hgure. However, as indicated by the curved arrows in the hgure, there is also feedback of information from later steps to earlier ones, such that the whole process can lead to iterative rehnement of the reaction mechanism. There are 

Group Additivity J Quantum Chemistry J Analogy/Estimation J 

Sensitivity Anaiysis Rate/Fiux Analysis Comparison to Experiment 

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The common feature is the imposition of constraints on the overall chemical transformation, and the assembly of building blocks so that these constraints are met by the construct (reaction mechanism or pathway) as a whole. The constraints refer to the stoichiometry of the transformations, i.e., the reactants and products that are involved, along with their proportions. As we will see, there are different ways to formulate these constraints, and each way is suitable for different applications. 

M. Swibart, Constructing Reaction Mechanisms, Chapter 5, in Modelling of Chemical Reactions, ed. by R. Carr. Comprehensive Chemical Kinetics, vol. 42 (EIscvIct, Netherlands, 2007), pp. 189-246... 

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