Welcome to Open Anharmonic!

Open Anharmonic is a Python 3 wrapper for computational chemistry software packages intended to enable VPT2 computation of anharmonic vibrational constants. The code is still in the preliminary stages of development; no VPT2 functionality is yet available.

Other types of calculations are under consideration.

An adjunct goal of the project is to expose an API providing convenient access to various results of standalone calculations, as well as tools to manipulate those results. In particular, OpanXYZ and the subclasses of SuperOpanGrad and SuperOpanHess are anticipated to be particularly useful.

Due to the large number of possible variations of computational runs, parsing of output files is challenging, and only a small number of run types have been implemented to date. More are planned, but are currently low priority.

Open Anharmonic is available on PyPI as opan:

pip install opan

See the dependencies page for package dependencies and compatible versions. Note that due to common complications on Windows systems, dependencies are NOT set to automatically install.

The source repository for Open Anharmonic can be found at:

https://www.github.com/bskinn/opan

Bug reports and feature requests can be submitted as GitHub Issues. Other feedback is welcomed at:

bskinn at alum dot mit dot edu

Contents

• User’s Guide
• API
• Notational and Algebraic Conventions
• Supported Software Packages
• Dependencies
• Units of Measure
• References
• Documentation To-Do

Indices and Tables

• Index
• Module Index
• Search Page