Formation of a quasi-solid structure by intercalated noble gas atoms in pores of Cu(I)-MFU-4l metal-organic framework.

The primary adsorption sites for Kr and Xe within the large-pore metal-organic framework Cu(I)-MFU-4l have been investigated by high-resolution synchrotron powder diffraction, revealing an enormous number of adsorption sites: in total, 10 crystallographically different positions for Xe and 8 positions for Kr were localized, the first five of which are located near metal atoms and the organic linker, and the remaining sites form a second adsorption layer in the pores.