Observation of gas molecules adsorbed in the nanochannels of porous coordination polymers by the in situ synchrotron powder diffraction experiment and the MEM/Rietveld charge density analysis

Microporous coordination polymers have attracted attention for their numerous nanotechnology and engineering applications. Nano-coordination space provides some unique properties and functions that could never be realized in conventional porous materials. For the strategy of rational designs and the syntheses of novel porous coordination polymers, the structural information of adsorbed guest molecules inside the nanopores and the host framework is very important. In the present study, we describe the technique of the direct observation of gas molecules adsorbed in the nanochannels of porous coordination polymers by the in situ synchrotron powder diffraction measurement of gas adsorption and the maximum entropy method (MEM)/Rietveld charge density analysis. Specific alignment and properties of molecular oxygen obtained by gas adsorption in the nano-coordination space are revealed.