Efficient screening for enhanced Xe/Kr separation

The separation of xenon (Xe) and krypton (Kr), being an energy-intensive process, has attracted considerable research interest in developing alternative separation methods and materials over the past two decades. Considerable progress has been achieved in discovering sorbent materials with high Xe/Kr selectivity. Due to their tunable pore geometries and interaction strengths, metal-organic frameworks (MOFs) have gained consensus as promising alternatives. For this goal, computational screening methods have been widely adopted to accelerate the discovery of high-performing candidates. However, the computational cost of brute-force screening involving adsorption simulations for millions of structures is prohibitive. Therefore, a practical approach is to partition large-scale screening into manageable subsets focusing on materials with shared chemical features. To conserve computational resources, applying reasonable filters on pore-related geometric features demonstrating significant variation is advisable. Based on these considations, we present a ligand-focused screening strategy employing preliminary geometric filters, including a pore-limiting diameter (PLD) ranging from 3.3 to 8.2 Å and a largest cavity diameter (LCD)/PLD ratio between 1 and 2, together with the restriction to single-ligand-assembled MOFs to facilitate structure-property interpretation. The procedure is exemplified using the ligand 1,1,2,2-tetra(4-carboxyphenyl)ethylene (H