alpha-lead tellurite from single-crystal data

作者：Zavodnik Valery E^*; Ivanov Sergey A; Stash Adam I

来源：Acta Crystallographica Section E-Structure Reports Online, 2008, 64: I16-U10.

DOI：10.1107/S1600536808003267

The crystal structure of the title compound, alpha-PbTeO3 ( PTO), has been reported previously by Mariolacos [ Anz. Oesterr. Akad. Wiss. Math. Naturwiss. Kl. ( 1969), 106, 128-130], refined on powder data. The current determination at room temperature from data obtained from single crystals grown by the Czochralski method shows a significant improvement in the precision of the geometric parameters when all atoms have been refined anisotropically. The selection of a centrosymmetric (C2/c) structure model was confirmed by the second harmonic generation test. The asymmetric unit contains three formula units. The structure of PTO is built up of three types of distorted [PbOx] polyhedra (x=7 and 9) which share their O atoms with TeO3 pyramidal units. These main anionic polyhedra are responsible for establishing the two types of tunnel required for the stereochemical activity of the lone pairs of the Pb2+ and Te4+ cations.

• 出版日期2008-3