Merohedral icosahedral M₄₈ (M = Co^II, Ni^II) cage clusters supported by thiacalix[4]arene

Abstract

Cage clusters are a discrete chemically and topologically diverse family of molecule-based functional materials. Presented here are two isostructural M₄₈ (M = Co^II for <b>LSHU01</b>, Ni^II for <b>LSHU02</b>) cage clusters with a merohedral icosahedral cage structure featuring 12 M₄-TC4A (H₄TC4A, <i>p-tert</i>-butylthiacalix[4]arene) second building units as vertices and 18 asymmetric 5-(1<i>H</i>-tetrazol-1-yl)isophthalate ligands as faces. They are the highest-nuclearity cage compounds of Co^II and Ni^II. The activated Co₄₈ cage exhibited high selectivity in the sorption of C₃H₈ over CH₄ under ambient conditions. Frequency response experiments indicated that the extrinsic voids and matrix interface of the activated crystalline samples are primarily responsible for the observed gas adsorption performance.