title: Ba2Gd2(Si4O13): a silicate with finite Si4O13 chains.
abstract: The title compound, dibarium digadolinium(III) tetrasilicate, crystallized from a molybdate-based flux. It represents a new structure type and contains finite zigzag-shaped C(2)-symmetric Si(4)O(13) chains and Gd(2)O(12) dimers built of edge-sharing GdO(7) polyhedra. The [9+1]-coordinated Ba atoms are located in voids in the atomic arrangement. All atoms are in general positions except for one O atom, which lies on a twofold axis. The structure is compared with those of the few other known tetrasilicates.
authors.affiliation: Universität Wien, Institut für Mineralogie und Kristallographie, Geozentrum, Althanstrasse 14, A-1090 Wien, Austria. maria.wierzbicka@univie.ac.at
authors.forename: Maria
authors.initials: M
authors.lastname: Wierzbicka-Wieczorek
authors.forename: Uwe
authors.initials: U
authors.lastname: Kolitsch
authors.forename: Ekkehart
authors.initials: E
authors.lastname: Tillmanns