title: Preparation and morphology of pyramidal MFI single-crystal segments.
abstract: Single-crystal segments of tetra-n-propylammonium-templated Silicalite-1 and ZSM-5 were prepared by postsynthetic treatment of twinned MFI prisms. Microwave irradiation of the parent crystallites in alkaline solution containing hydrogen peroxide, followed by ultrasound treatment, led to disintegration of the zeolite prisms. The resulting wedge-shaped crystal segments proved to be single crystals of excellent crystallinity as shown by optical and X-ray investigations. The hydroxyl ions, compensating the positive charges of the tetrapropylammonium cations, were located by single-crystal structure refinement in template-containing Silicalite-1 and ZSM-5 but absent from the calcined samples.
authors.affiliation: Max-Planck-Institut für Kohlenforschung, Kaiser-Wilhelm-Platz 1, D-45470 Mülheim a.d. Ruhr, Germany. wolfgang.schmidt@kofo.mpg.de
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Schmidt
authors.forename: Ursula
authors.initials: U
authors.lastname: Wilczok
authors.forename: Claudia
authors.initials: C
authors.lastname: Weidenthaler
authors.forename: Olaf
authors.initials: O
authors.lastname: Medenbach
authors.forename: Richard
authors.initials: R
authors.lastname: Goddard
authors.forename: Gernot
authors.initials: G
authors.lastname: Buth
authors.forename: Alexander
authors.initials: A
authors.lastname: Cepak