Distinctive Three-Step Hysteretic Sorption of Ethane with In Situ Crystallographic Visualization of the Pore Forms in a Soft Porous Crystal

A soft porous Zn­(II)–MOF (1) displays distinctive three-step hysteretic breathing behavior under ethane gas pressure at ambient temperatures. In situ single-crystal X-ray diffraction analysis was carried out at 298 K using an environmental gas cell in order to elucidate the different porous forms of the breathing framework under ethane gas. The three different phases were further characterized by pressure-gradient differential scanning calorimetry and variable pressure powder X-ray diffraction analysis.