Crystals of Ni 6 L 12 Ellipsoidal Tubes as Single-Crystal-to-Single-Crystal Adsorption Matrix: Penetrative Study of Self-Assembled Crystals vs Guest-Exchanged Crystals.

Informative similarities/differences between self-assembled and single-crystal-to-single-crystal (SCSC) guest-exchanged crystals based on both the molecular structure and adsorption nature are observed. The self-assembly of Ni(ClO 4 ) 2 with a dicyclopentyldi(pyridine-3-yl)silane bidentate ligand (L) in a mixture of toluene and acetonitrile gives rise to purple crystals consisting of double-stranded ellipsoidal tubes, [Ni 6 (ClO 4 ) 4 (CH 3 CN) 8 L 12 ]·8ClO 4 ·4CH 3 CN·5C 7 H 8 . The coordinated acetonitriles as well as the solvates are removed at 170 °C to transform the purple crystals into blue crystals of [Ni(ClO 4 ) 2 L 2 ] n that return to the original crystals in the mixture of toluene and acetonitrile. Further, the toluene and acetonitrile solvates of the original crystals are replaced by o -, m -, and p -xylene isomers within 5 min in a SCSC manner. In the present study, SCSC xylene-exchanged crystals were compared with crystals obtained from direct self-assembly in a mixture of each xylene isomer and acetonitrile.