A Porous Metal–Organic Framework with Dynamic Pyrimidine Groups Exhibiting Record High Methane Storage Working Capacity

We have realized a new porous metal–organic framework UTSA-76a with pyrimidine groups on the linker, exhibiting high volumetric methane uptake of ∼260 cm³ (STP) cm^–3 at 298 K and 65 bar, and record high working capacity of ∼200 cm³ (STP) cm^–3 (between 5 and 65 bar). Such exceptionally high working capacity is attributed to the central “dynamic” pyrimidine groups within UTSA-76a, which are capable of adjusting their orientations to optimize the methane packing at high pressure, as revealed by computational studies and neutron scattering experiments.