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<table>The coefficient of the thermal expansion <svg height="11.825" id="M48" style="vertical-align:-3.27605pt" version="1.1" viewbox="0 0 17.200001 11.825" width="17.200001" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink">
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<g transform="matrix(.012,0,0,-.012,9.713,11.763)"><path d="M559 163q-23 -66 -68 -163h-474l6 26q62 4 79.5 19.5t28.5 75.5l78 409q7 35 8.5 49t-8 25t-24 13t-51.5 5l5 28h266l-6 -28q-65 -5 -79.5 -18t-25.5 -74l-76 -406q-10 -57 14 -75q12 -13 96 -13q93 0 126 29q41 40 76 109z" id="x1D43F"></path></g>
</svg> caused by the lattice vibration as a function of the temperature. </table>

Advances in Condensed Matter Physics

fig2

Figure 2

Figure 2: Origin of the Giant Negative Thermal Expansion in <svg style="vertical-align:-4.47125pt;width:163.2625px;" id="M1" height="21.612499" version="1.1" viewBox="0 0 163.2625 21.612499" width="163.2625"      xmlns:xlink="http://www.w3.org/1999/xlink" xmlns="http://www.w3.org/2000/svg">
	
		
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