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arXiv · 1707.09572

Automated transition state theory calculations for high-throughput kinetics

Pierre L. Bhoorasingh·Belinda L. Slakman·Fariba Seyedzadeh Khanshan·Jason Y. Cain·Richard H. West
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Abstract

A scarcity of known chemical kinetic parameters leads to the use of many reaction rate estimates, which are not always sufficiently accurate, in the construction of detailed kinetic models. To reduce the reliance on these estimates and improve the accuracy of predictive kinetic models, we have developed a high-throughput, fully automated, reaction rate calculation method, AutoTST. The algorithm integrates automated saddle-point geometry search methods and a canonical transition state theory kinetics calculator. The automatically calculated reaction rates compare favorably to existing estimated rates. Comparison against high level theoretical calculations show the new automated method performs better than rate estimates when the estimate is made by a poor analogy. The method will improve by accounting for internal rotor contributions and by improving methods to determine molecular symmetry.

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Pierre L. Bhoorasingh, Belinda L. Slakman, Fariba Seyedzadeh Khanshan, Jason Y. Cain, Richard H. West. 2017-07-30. Automated transition state theory calculations for high-throughput kinetics. https://doi.org/10.1021/acs.jpca.7b07361

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