Coarse-Grained Models for Automated Fragmentation and Parametrization of Molecular Databases

We calibrate coarse-grained interaction potentials suitable for screening large data sets in top-down fashion. Three new algorithms are introduced: (i) automated decomposition of molecules into coarse-grained units (fragmentation); (ii) Coarse-Grained Reference Interaction Site Model—Hypernetted Chain (CG RISM-HNC) as an intermediate proxy for dissipative particle dynamics(DPD); and (iii) a simple top-down coarse-grained interaction potential/model based on activity coefficienttheories from engineering (using COSMO-RS). We find that the fragment distribution follows Zipf and Heaps scaling laws. The accuracy in Gibbs energy of mixing calculations is a few tenths of a kilocalorie per mole. As a final proof of principle, we use full coarse-grained sampling through DPD thermodynamics integrationto calculate log POW for 4627 compounds with an average error of 0.84 log unit. The computational speeds per calculation are a few seconds for CG RISM-HNC and a few minutes for DPD thermodynamic integration.