# 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.

## 1.1. About CanTherm

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

## 1.2. License

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)
Permission is hereby granted, free of charge, to any person obtaining a
copy of this software and associated documentation files (the 'Software'),
to deal in the Software without restriction, including without limitation
the rights to use, copy, modify, merge, publish, distribute, sublicense,
and/or sell copies of the Software, and to permit persons to whom the
Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.
THE SOFTWARE IS PROVIDED 'AS IS', WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
DEALINGS IN THE SOFTWARE.