Broad chemical transferability in structure-based coarse-graining
Compared to top-down coarse-grained (CG) models, bottom-up approaches are capable of offering higher structural fidelity. This fidelity results from the tight link to a higher resolution reference, making the CG model chemically specific. Unfortunately, chemical specificity can be at odds with compound-screening strategies, which call for transferable parameterizations. Here, we present an approach to reconcile bottom-up, structure-preserving CG models with chemical transferability. We consider the bottom-up CG parameterization of 3441 C7O2 small-molecule isomers. Our approach combines atomic representations, unsupervised learning, and a large-scale extended-ensemble force-matching parameterization. We first identify a subset of 19 representative molecules, which maximally encode the local environment of all gas-phase conformers. Reference interactions between the 19 representative molecules were obtained from both homogeneous bulk liquids and various binary mixtures. An extended-ensemble parameterization over all 703 state points leads to a CG model that is both structure-based and chemically transferable. Remarkably, the resulting force field is on average more structurally accurate than single-state-point equivalents. Averaging over the extended ensemble acts as a mean-force regularizer, smoothing out both force and structural correlations that are overly specific to a single-state point. Our approach aims at transferability through a set of CG bead types that can be used to easily construct new molecules while retaining the benefits of a structure-based parameterization.
None
@article{Kanekal_2022,
doi = {10.1063/5.0104914},
url = {https://doi.org/10.1063%2F5.0104914},
year = 2022,
month = {sep},
publisher = {{AIP} Publishing},
volume = {157},
number = {10},
pages = {104102},
author = {Kiran H. Kanekal and Joseph F. Rudzinski and Tristan Bereau},
title = {Broad chemical transferability in structure-based coarse-graining},
journal = {The Journal of Chemical Physics}
}