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\subsubsection{\texorpdfstring{225 GST}{225 GST}}
\label{sec:225_gst}


Using \emph{ab initio} density functional theory, we have investigated
the phase transition of Ge\textsubscript{2}Sb\textsubscript{2}Te\textsubscript{5}
between its crystalline and amorphous phases. blah blah

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