G. Redhammer, G. Tippelt
Oct 15, 2013
Citations
0
Influential Citations
5
Citations
Journal
Acta crystallographica. Section C, Crystal structure communications
Abstract
Dilithium tetragermanate is orthorhombic, space group P2(1)ca, at 298 K, and is thus in a polar and probably a ferroelectric state. The structure contains two independent Li, four Ge and nine O atoms, all on general positions with site symmetry 1. Three tetrahedrally coordinated Ge positions form crumpled crankshaft-like chains, forming sheets within the ac plane, and these are interconnected by the fourth, octahedrally coordinated, Ge sites along the b direction. The GeO4 tetrahedra and GeO6 octahedra form a three-dimensional framework containing two different cavities, hosting the two 4+1-coordinated Li sites. Cooling to 90 K does not alter the space-group symmetry; the tetrahedral chains behave as a rigid unit and changes occur mainly within the Li coordination spheres.