Tin clusters that do not melt: Calorimetry measurements up to 650 K
نویسندگان
چکیده
Recent theoretical studies fK. Joshi, D. G. Kanhere, and S. A. Blundell, Phys. Rev. B 67, 235413 s2003dg predict that Sn20 melts at around 1200 K. We have performed calorimetry measurements on unsupported Sn18 + , Sn19 + , Sn20 + , and Sn21 + in an effort to test this prediction. We find that these tin clusters disappear well below their predicted melting temperature due to dissociation. Calorimetry measurements performed up to around 650 K show some small features swhich may be due to localized structural changesd but no clear melting transitions. Hence, tin clusters in this size regime do not melt—they sublime.
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