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arXiv · 2409.10505

Machine Learning Optimization of non-Kasha Behavior and of Transient Dynamics in Model Retinal Isomerization

Davinder Singh·Chern Chuang·Paul Brumer
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Abstract

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.

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Davinder Singh, Chern Chuang, Paul Brumer. 2024-09-16. Machine Learning Optimization of non-Kasha Behavior and of Transient Dynamics in Model Retinal Isomerization. https://arxiv.org/abs/2409.10505

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