KSbO(Ge0.32Si0.68)O-4, a KTP isomorph
Artikel i vetenskaplig tidskrift, 2001

A structural model of potassium antimony germanate/silicate (0.32/0.68), KSbO(Ge0.32Si0.68)O-4, has been determined at room temperature. KSbO(Ge0.32Si0.68)O-4 belongs to the KTiOPO4 (KTP) isomorphic family and is composed of SbO6 octahedra (site symmetry (1) over bar and 2) arranged in helical chains bridged by (Ge/Si)O-4 tetrahedra. Germanium and silicon have a similar distribution in the crystallographically independent tetrahedra (site symmetry 2). The structure contains large cavities occupied by the K atom. Two partially occupied potassium positions have been identified 1.273 (8) Angstrom apart, with an indication of a third potassium position between them. At room temperature, KSbO(Ge0.32Si0.68)O-4 crystallizes in the paraelectric phase of space group Pnan. This phase is found at elevated temperatures for almost all KTiOPO4 isomorphic compounds and KSbO(Ge0.32Si0.68)O-4 is the second isomorph that is paraelectric at room temperature.

Crystal Structure

KTiOPO4 Isostructure

Författare

Stefan Norberg

Institutionen för oorganisk kemi

Göran Svensson

Institutionen för oorganisk kemi

Jörgen Albertsson

Institutionen för oorganisk kemi

Acta Crystallographica Section C: Crystal Structure Communications

0108-2701 (ISSN) 1600-5759 (eISSN)

Vol. 57 5 510-512

Ämneskategorier

Oorganisk kemi