Physical Chemistry

Enhanced Sampling Aided Design of Molecular Photoswitches



Advances in the evolving field of atomistic simulations provide continuous insights for the design and fundamental understanding of novel molecular photoswitches. Here, we use state-of-the-art enhanced simulation techniques to unravel the complex, multistep chemistry of donor-acceptor Stenhouse adducts (DASAs), revealing a plethora of newly discovered thermal pathways. We use enhanced sampling simulations to drive reaction discovery, followed by refinement of newly observed pathways with more accurate ab initio electronic structure calculations, and then structural modifications to introduce design principles in new generations of DASAs. We illustrate tunability of these newly discovered reactions, leading to a potential avenue for controlling DASA dynamics through multiple external stimuli. Overall, these insights could offer alternative routes to increase the efficiency and control of DASA’s photoswitching mechanism, providing new elements to design more complex light-responsive materials.


Thumbnail image of Main-Text.pdf

Supplementary material

Thumbnail image of SI.pdf
Supplemental Information
Computational Details; reaction discovery workflow; summary of the discovered phase starting from A and A’; energies of the ground-state minima and transition states for Meldrum’s acid first-generation DASAs; relative energies of B, E, F, and G minima between the 1st, 2nd and 3rd generation DASAs; energies of the ground-state minima and transition states for compound 3d; atoms included in the definition of the collective variable max; simulated UV electronic absorption spectra of compound 1a and 2b.