Designing a model of retinal isomerization in Rhodopsin, the first step in vision, that accounts for both experimental transient and stationary state observables is challenging. Here, multi-objective Bayesian optimization is employed to refine the parameters of a minimal two-state-two-mode (TM) model describing the photoisomerization of retinal in Rhodopsin. With an appropriate selection of objectives, the optimized retinal model predicts excitation wavelength-dependent fluorescence spectra that closely align with experimentally observed non-Kasha behavior in the non-equilibrium steady state. Further, adjustments to the potential energy surface within the TM model reduce the discrepancies across the time domain. Overall, agreement with experimental data is excellent.
@article{arxiv.2409.10505,
title = {Machine Learning Optimization of non-Kasha Behavior and of Transient Dynamics in Model Retinal Isomerization},
author = {Davinder Singh and Chern Chuang and Paul Brumer},
journal= {arXiv preprint arXiv:2409.10505},
year = {2024}
}