# 1. Introduction¶

CanTherm is a tool for computing the thermodynamic properties of chemical species and high-pressure-limit rate coefficients for chemical reactions using the results of a quantum chemistry calculation. Thermodynamic properties are computed using the rigid rotor-harmonic oscillator approximation with optional corrections for hindered internal rotors. Kinetic parameters are computed using canonical transition state theory with optional tunneling correction.

CanTherm can also estimate pressure-dependent phenomenological rate coefficients $$k(T,P)$$ for unimolecular reaction networks of arbitrary complexity. The approach is to first generate a detailed model of the reaction network using the one-dimensional master equation, then apply one of several available model reduction methods of varying accuracy, speed, and robustness to simplify the detailed model into a set of phenomenological rate coefficients. The result is a set of $$k(T,P)$$ functions suitable for use in chemical reaction mechanisms.

CanTherm is written in the Python programming language to facilitate ease of development, installation, and use.

CanTherm is provided as free, open source code under the terms of the MIT/X11 License. The full, official license is reproduced below

Copyright (c) 2002-2017 Prof. William H. Green (whgreen@mit.edu),
Prof. Richard H. West (r.west@neu.edu) and the RMG Team (rmg_dev@mit.edu)

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copy of this software and associated documentation files (the 'Software'),
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