SINGLE CRYSTALS GROWTH IN THE HOMOGENEITY REGION OF LOW-TEMPERATURE MODIFICATION OF Ag8GeS6

Cationic ion-conductors have found wide practical application as electric batteries. Among them the lithium-ion batteries are most common commercially used. However, research is being actively carried out to improve safety of these possible compounds, silver-containing phases attractive, since silver-ions, along with high values ionic conductivity in solid-state, haven’t chemical activity like same alkali metal-ions. Realization crystal structure necessary for effective ion transport observed compounds argyrodite - a group ternary chalcogenides and quaternary chalcohalogenides multi-charged cations (Ge4+, Si4+, P5+). In this work, study heterovalent cationic P5+→Ge4+ substitution Ag8GeS6 enriched region was out. Single crystals Ag8-x(Ge1-xPx)S6 (x = 0.25; 0.5) solid solutions were grown by method directional crystallization using solution-melt technique. The single characterized absence macrodefects, dark gray color metallic luster, dimensions l ~3 cm d 1.2 cm. Using Rietveld refinement method, established lattice parameters determined. Established, that crystallize orthorhombic system primitive cell space Pna21.
 Keywords: argyrodites; crystals; crystallization; phase analysis.