Periodic Reporting for period 1 - DIEinPEACE (Double Incremental Expansion in Potential Energies from Automized Computational Exploration)
Reporting period: 2019-05-01 to 2021-04-30
In this project, we aimed at bridging this gap and finding ways to accurate and fast theoretical computations of PESs for large molecular systems of biochemical interest. To that end, we: i) developed new theoretical approaches; ii) implemented them in open-source program codes; iii) demonstrated their performance on test molecular systems.
The new approaches show a considerable reduction in the computational cost of the overall PES construction compared to the known and more conventional methods and, therefore, can target larger molecular systems than previously accessible. Further computational gain can be reached by combining the developed methodologies in a unified framework making us one step closer to theoretical simulations of large biochemical systems.
Even larger molecular systems can be targeted by combining the above-mentioned approaches with density embedding techniques, which describe large surrounding molecular environments by means of embedding potentials. Another advantage of these techniques is that they provide an easy route to calculations of diabatic PESs. In the current project, I investigated the performance of density embedding techniques for diabatization on molecular systems including up to 2000 atoms. These test calculations were compared versus experimental results and shown to be sufficiently accurate for molecular properties such as spin densities. Additional work (in progress) was carried out to further improve and generalize this method to multiple electronic states. End results of this project were published in the high-ranked peer-review Journal of Physical Chemistry B and uploaded to the ChemRxiv research data repository. The described methodology was made publicly available by implementing it in the open-source quantum chemistry Serenity program.