Density Gradation of Open Metal Sites in the Mesospace of Porous Coordination Polymers

The prevalence of the condensed phase, interpenetration, and fragility of mesoporous coordination polymers (meso-PCPs) featuring dense open metal sites (OMSs) place strict limitations on their preparation, as revealed by experimental and theoretical reticular chemistry investigations. Herein, we propose a rational design of stabilized high-porosity meso-PCPs, employing a low-symmetry ligand in combination with the shortest linker, formic acid. The resulting dimeric clusters ( PCP-31 and PCP-32 ) exhibit high surface areas, ultrahigh porosities, and high OMS densities (3.76 and 3.29 mmol g –1, respectively), enabling highly selective and effective separation of C 2 H 2 from C 2 H 2 /CO 2 mixtures at 298 K, as verified by binding energy (BE) and electrostatic potentials (ESP) calculations.