Multi-Reference Wavefunction Overlap as a Metric for Dynamic Method Selection

Loreti et al. (2024) developed WFOT to quantify overlaps between single- and multi-reference wavefunctions, but it’s currently a diagnostic tool. This research would transform WFOT into an active controller: during molecular dynamics or PES scans, the overlap metric would trigger automatic method switching (e.g., from TD-DFT to CASSCF) when multi-reference character exceeds a threshold. This bridges the conflict between scalable single-reference methods (Wei et al. 2024) and accurate multi-reference approaches (Tecmer & Boguslawski 2022). Unlike static workflows, it adapts to bond-breaking or excited-state transitions in real time, enabling efficient simulations of photochemistry (e.g., acetylacetone dynamics in Loreti’s paper) with adaptive accuracy.

References:

1. Scalable Ab Initio Electronic Structure Methods with Near Chemical Accuracy for Main Group Chemistry.. Yujing Wei, Sibali Debnath, John L. Weber, Ankit Mahajan, D. Reichman, R. Friesner (2024). Journal of Physical Chemistry A.
2. Geminal-based electronic structure methods in quantum chemistry. Toward a geminal model chemistry.. P. Tecmer, Katharina Boguslawski (2022). Physical Chemistry, Chemical Physics - PCCP.
3. WFOT: A Wave Function Overlap Tool between Single- and Multi-Reference Electronic Structure Methods for Spectroscopy Simulation.. Alessandro Loreti, V. M. Freixas, Davide Avagliano, F. Segatta, Huajing Song, Sergei Tretiak, S. Mukamel, M. Garavelli, N. Govind, A. Nenov (2024). Journal of Chemical Theory and Computation.