Accelerating the discovery of nanoporous gas separation materials via Coulomb-enhanced classical density functional...

The design of advanced nanoporous materials for gas separations, such as carbon capture and alkyne purification, is increasingly driven by high-throughput screening. However, the accurate description of electrostatic interactions in porous frameworks remains challenging and can introduce sizable deviations between predicted and experimental performance, thereby hindering rational materials design. To address this gap, we present a computational framework, compatible with standard force fields under appropriate charge assignments, that explicitly incorporates a point-charge model to capture adsorbate-framework long-range Coulomb interactions via the Ewald summation technique within the external potential of classical density functional theory (cDFT), enabling adsorption prediction for common polar or quadrupolar gas molecules. The resulting Coulomb-enhanced cDFT (QcDFT) shows closer agreement with GCMC and experimental adsorption data than existing cDFT variants, and was applied to 689 CO₂/MOF adsorption cases and nearly 10 000 CoRE MOF 2019 structures for C₂H₂/CO₂ screening. By further integrating the string method, QcDFT allows for efficient prediction of adsorption selectivity and rapid estimation of self-diffusion coefficients, achieving up to three orders of magnitude acceleration relative to conventional molecular dynamics simulations. This combination of speed and accuracy makes QcDFT well suited to large-scale nanoporous materials screening, bridging atomic-scale adsorption mechanisms with separation-relevant candidate selection.