title: Dynamics of chloromethanes in cryptophane-E inclusion complexes: a 2H solid-state NMR and X-ray diffraction study.
abstract: In this paper, we present a variable temperature (2)H solid-state NMR investigation of cryptophane-E:chloroform and cryptophane-E:dichloromethane inclusion complexes. The (2)H line shapes and nuclear spin relaxation rates were analyzed in terms of the distribution of C-D bond orientations and the time scale of the guest dynamics. It was found that encaged chloroform produces broad (2)H spectra, and that its reorientation is relatively slow with a correlation time of approximately 0.17 mus at 292 K. In contrast, the (2)H line shapes of encaged dichloromethane are narrow and the motion of this guest molecule is fast with a correlation time of approximately 1.4 ps at 283 K. The (2)H NMR data were complemented by an X-ray diffraction study of the cryptophane-E:dichloromethane structure, which was utilized in the analysis of the NMR parameters.
authors.affiliation: Department of Physical, Inorganic, and Structural Chemistry, Arrhenius Laboratory, Stockholm University, SE-106 91 Stockholm, Sweden.
authors.forename: Oleg
authors.initials: O
authors.lastname: Petrov
authors.forename: Zdenek
authors.initials: Z
authors.lastname: Tosner
authors.forename: Ingeborg
authors.initials: I
authors.lastname: Csöregh
authors.forename: Jozef
authors.initials: J
authors.lastname: Kowalewski
authors.forename: Dick
authors.initials: D
authors.lastname: Sandström