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 C2H2 from C2H2/CO2 mixtures at 298 K, as verified by binding energy (BE) and
electrostatic potentials (ESP) calculations.