Cluster melting magic number

H. Haberland, T. Hippier, J. Donges, O. Kostko, M. Schmidt, B. von Issendorlf, Melting of sodium clusters where do the magic numbers come from Phys. Rev. Lett. 94(3), 035701 (2005)... 

Abundance anomalies as discussed above relate to unique atomic structures. Molten clusters will not exhibit magic numbers. This has been utilized to determine melting temperatures of clusters in the gas phase. If sodium clusters are thermalized in warm helium and then allowed to effuse into vacuum, no magic numbers related to atomic structure are observed. If the gas is cooled to 307 K (83% of the bulk melting temperature), magic numbers appear for clusters of size n > 6000. They extend to smaller clusters if the temperature is lowered further. Smaller clusters melt at lower temperatures. Molten sodium clusters show a different sequence of magic numbers as explained in the following section. 

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