title: In situ X-ray snapshot analysis of transient molecular adsorption in a crystalline channel.
abstract: Molecular adsorption is a fundamental phenomenon in porous materials and is usually characterized by the efficiency and selectivity of molecular separations and reactions. However, for functional porous materials, analysis of the dynamic behaviour of molecular adsorbents is a major challenge. Here, we use in situ single-crystal X-ray diffraction to analyse multi-step molecular adsorption in a crystalline nanochannel of a metal-macrocycle framework. The pore surface of the metal-macrocycle framework crystal contains five different enantiomerically paired binding pockets, to which the adsorption of a (1R)-1-(3-chlorophenyl)ethanol solution was monitored with time. The resulting X-ray snapshot analyses suggest that the guest adsorption process takes a two-step pathway before equilibrium, in which the guest molecule is temporarily trapped by a neighbouring binding site. This demonstrates the potential for using X-ray analyses to visualize a transient state during a non-covalent self-assembly process.
authors.affiliation: Department of Chemistry, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
authors.forename: Ryou
authors.initials: R
authors.lastname: Kubota
authors.affiliation: Department of Chemistry, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
authors.forename: Shohei
authors.initials: S
authors.lastname: Tashiro
authors.affiliation: Rigaku Co. Ltd, 3-9-2 Matsubaracho, Akishima, Tokyo 196-8666, Japan.
authors.forename: Motoo
authors.initials: M
authors.lastname: Shiro
authors.affiliation: Department of Chemistry, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan.
authors.forename: Mitsuhiko
authors.initials: M
authors.lastname: Shionoya