Computational Screening of Porous Organic Molecules\nfor Xenon/Krypton Separation

Abstract

We\nperformed a computational screening of previously reported porous\nmolecular materials, including porous organic cages, cucurbiturils,\ncyclodextrins, and cryptophanes, for Xe/Kr separation. Our approach\nfor rapid screening through analysis of single host molecules, rather\nthan the solid state structure of the materials, is evaluated. We\nuse a set of tools including in-house software for structural evaluations,\nelectronic structure calculations for guest binding energies, and\nmolecular dynamics and metadynamics simulations to study the effect\nof the hosts’ flexibility upon guest diffusion. Our final results\nconfirm that the <b>CC3</b> cage molecule, previously reported\nas high performing for Xe/Kr separation, is the most promising of\nthis class of materials reported to date. The Noria molecule was also\nfound to be promising, and we therefore synthesized two related Noria\nmolecules and tested their performance for Xe/Kr separation in the\nlaboratory.