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\subsubsection{\texorpdfstring{Ge\$\_2\$Sb\$\_2\$Te\$\_5\$}{Ge_2Sb_2Te_5}}
\label{sec:ge_2sb_2te_5}


Using \emph{ab initio} density functional theory, we have investigated
the phase transition of Ge$_2$Sb$_2$Te$_5$ between its crystalline
and amorphous phases. blah blah

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