1. Introduction

Arkane (Automated Reaction Kinetics and Network Exploration) 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.

Arkane 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. More information is available at Allen et al..

Arkane is developed and distributed as part of RMG-Py, but can be used as a stand-alone application for Thermochemistry, Transition State Theory, and Master Equation chemical kinetics calculations.

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

Additional theoretical background can be found at RMG’s Theory Guide.

1.1. License

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

Copyright (c) 2002-2023 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
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FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
DEALINGS IN THE SOFTWARE.