OMNI-P2x is a universal neural network potential for excited-state simulations. It approaches TD-DFT quality predictions, e.g., for UV/vis absorption spectra at a fraction of cost. OMNI-P2x is faster and more accurate than semiempirical QM methods such as TD-DFTB.
You can use OMNI-P2x in MLatom via Aitomic add-on, either online via a web browser or locally on your computer. Below are the details.
It is convenient to do calculations with OMNI-P2x via a web browser, where two options are available:
- Aitomistic Hub - provides a convenient web interface for performing simulations, with limited free resources mainly for demo purposes (recommended).
- XACS cloud - a less convenient but a time-proven solution with generous free computational resources for academic users.
You can request a ready-to-use implementation in the Aitomic package (which builds upon MLatom by providing add-ons for unpublished features like this one), it is free for academic users subject to a license agreement. The source code is planned to be openly released in MLatom under the MIT license upon the acceptance of the manuscript in the journal of our choice.
Alternatively, the model weights are available in this repository under the folder model_weights. You can adjust MLatom's source code as described in the preprint (see citation below) to load the weights and use them.
Example usage for predicting SPC spectra is provided in the form of a Jupyter notebook.
- Mikolaj Martyka, Xin-Yu Tong, Joanna Jankowska, and Pavlo O. Dral. OMNI-P2x: A Universal Neural Network Potential for Excited-State Simulations. 2025, to be submitted. Preprint on ChemRxiv: https://doi.org/10.26434/chemrxiv-2025-j207x (2025-04-16)