ThermoScreening 0.2.0

A Python package for screening molecules for their thermochemical properties.

ThermoScreening

ThermoScreening calculates thermochemical properties for molecular systems and provides a foundation for screening molecule sets. It currently supports thermochemistry workflows from DFTB+ inputs and exposes Python APIs for reading coordinates, parsing vibrational data, and running thermodynamic post-processing.

Documentation

The documentation is published at https://molarverse.github.io/ThermoScreening/.

It (installation, usage, configuration, and the API reference) is built with Sphinx from the docs/ directory, and you can also build it locally:

python -m pip install -e ".[docs]"
python -m sphinx -b html docs docs/_build/html   # open docs/_build/html/index.html

Features

• Thermochemistry calculations for molecular systems
• DFTB+ geometry optimization, Hessian, and normal-mode integration
• Readers for DFTB+ .gen, XYZ, and vibrational frequency files
• Runtime type checking for public API calls
• Test coverage for parsing, thermochemistry, and optional DFTB+ execution paths

Installation

Install the package from a checkout:

python -m pip install .

For development and tests:

python -m pip install -e ".[test,lint]"

For a Conda-based development environment with all calculation backends (DFTB+, modes, xtb, tblite) included:

conda env create -f environment.yml
conda activate thermoscreening

Then thermo doctor should report every backend as found.

DFTB+ Setup

DFTB+ calculations require two external pieces:

1. The dftb+ and modes executables on PATH.
2. Slater-Koster parameter files downloaded separately from DFTB.org.

Install DFTB+ with Conda if it is not already available:

conda install -c conda-forge dftbplus

Download the default 3ob-3-1 Slater-Koster files into a user-local directory:

thermo setup-dftb

The command prints the DFTB_PREFIX export needed by DFTB+ and ThermoScreening:

export DFTB_PREFIX="$HOME/.local/share/thermoscreening/slakos/3ob-3-1/"

Add that line to your shell configuration for persistent use. Verify the setup with:

thermo doctor

ThermoScreening does not vendor Slater-Koster files. For custom installations, point the calculator to a parameter directory with DFTB_PREFIX or pass slako_dir explicitly:

from ThermoScreening.thermo.api import dftbplus_thermo

thermo = dftbplus_thermo(
    atoms,
    slako_dir="/path/to/3ob-3-1/",
)

The bundled DFTB+ parameters were removed from the repository because they are large, independently licensed scientific data. Keeping them external makes the package smaller and keeps parameter-set licensing explicit.

Usage

Run thermochemistry from an input file with the command-line entry point:

thermo path/to/thermo.in

Use the Python API when integrating ThermoScreening into another workflow:

from ThermoScreening.thermo.api import run_thermo

thermo = run_thermo(
    vibrational_frequencies,
    coord_file="geo_opt.xyz",
    temperature=298.15,
    pressure=101325,
    energy=electronic_energy,
    engine="dftb+",
)

print(thermo.total_gibbs_free_energy())

Testing

Run the full test suite:

python -m pytest -q

Run linting:

python -m pylint ThermoScreening

DFTB+ integration tests run only when the executables are available and DFTB_PREFIX points to a valid Slater-Koster directory. Otherwise they are skipped so the pure-Python test suite remains portable.

Citing

If you use ThermoScreening in research, cite the archived software release. Machine-readable citation metadata is available in CITATION.cff, which also powers GitHub's Cite this repository feature. Each GitHub release is archived by Zenodo and receives a version-specific DOI.

Roadmap

Planned work is tracked in GitHub issues rather than in this README. The tool supports the DFTB+, GFN-xTB (tblite) and native-xtb engines, implicit solvation, quasi-RRHO, batch screening with resume, and RDKit conformer generation; see the issue tracker for further enhancements.

License

ThermoScreening source code is licensed under the GNU Lesser General Public License v2.1 or later. See LICENSE.