Chemical engineering Density Functional Theory EDX elemental chemical mapping GGST Ge-rich GST Ge-rich GST alloys Ge-rich alloys Ge2Sb2Te5 Ge–Sb–Te Ge–Sb–Te/Sb2Te3 MOCVD PCM Raman Technology: general issues VLS amorphous phase core-shell crystallization crystallization temperature density functional theory electrical properties electronic properties embedded electronic memories embedded memory flexible substrates germanium telluride high-throughput calculations indium alloying kinetics