Structural transformation of Sb-based high-speed phase-change material

On heating, amorphous Ag_3.1In_3.7Sb_76.4Te_16.5 crystallizes at 416 K in an A7 structure type with atomic sites randomly occupied by the four constituent elements. At 545 K the compound decomposes into two crystalline phases: AgInTe₂ is stable up to the melting point, while Sb₈₉Te₁₁ has a modulated layer structure with a temperature-dependent layer period.