Understanding kinetics including reaction pathways and associated transition rates is an important yet difficult problem in numerous chemical and biological systems especially in situations with multiple competing pathways. When these high-dimensional systems are projected on low-dimensional coordinates often needed for enhanced sampling or for interpretation of simulations and experiments, one often ends up losing the kinetic connectivity of the underlying high-dimensional landscape. Thus in the low-dimensional projection metastable states might appear closer or further than they actually are. To deal with this issue, in this work we develop a formalism that learns a multi-dimensional yet minimally complex reaction coordinate (RC) for generic high-dimensional systems, such that when projected along this RC, all possible kinetically relevant pathways can be demarcated and the true high-dimensional connectivity is maintained. One of the defining attributes of our method lies in that it can work on long unbiased simulations as well as biased simulations often needed for rare event systems. We demonstrate the utility of the method by studying a range of model systems including conformational transitions in a small peptide Ace-Ala3-Nme, where we show how SGOOPderived two-dimensional and three-dimensional reaction coordinate can capture the kinetics for 23 and all 28 out of the 28more »
This content will become publicly available on September 23, 2023
Deterministic fabrication of 3D/2D perovskite bilayer stacks for durable and efficient solar cells
Solvents enable growth of phase-pure two-dimensional perovskites without dissolving three-dimensional perovskite substrates.
- Authors:
- ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; ; more »
- Award ID(s):
- 1719797
- Publication Date:
- NSF-PAR ID:
- 10399554
- Journal Name:
- Science
- Volume:
- 377
- Issue:
- 6613
- Page Range or eLocation-ID:
- 1425 to 1430
- ISSN:
- 0036-8075
- Sponsoring Org:
- National Science Foundation
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