title: Edge-sharing SiN4 Tetrahedra in the Highly Condensed Nitridosilicate BaSi7 N10.
abstract: The novel nitridosilicate BaSi7 N10 was obtained by the reaction of barium metal with Si(NH)2 in a special high-frequency furnace at 1650 °C. The single-crystal structure determination (a = 687.29(3), b = 671.29(3), c = 963.28(4) pm, β = 106.269(3)°, PC, Z = 2, R1 = 0.0497, wR2 = 0.0924) reveals a network structure of connected SiN4 tetrahedra. BaSi7 N10 is the first nitridosilicate with both corner and edge-sharing SiN4 tetrahedra. Unlike the situation in normal oxosilicates, vertex-sharing of SiN4 tetrahedra is not exclusively favored over edge-sharing. With a Si:N molar ratio of 7:10, BaSi7 N10 is the most highly condensed multinary nitridosilicate known and has almost the same degree of condensation as binary Si3 N4 .
authors.affiliation: Laboratorium für Anorganische Chemie der Universität, D-95440 Bayreuth (Germany), Fax: Int. code +(921)55-2788, e-mail: wolfgang.schnick@uni-bayreuth.de.
authors.forename: H
authors.initials: H
authors.lastname: Huppertz
authors.forename: W
authors.initials: W
authors.lastname: Schnick
keywords: high-temperature synthesis; network structures; nitridosilicates; silicon; structure elucidation