Cluster melting first order transition

Between temperatures of 28 and 29 K the rms bond length fluctuations of the 13-particle system increase dramatically. Similar results have been obtained for all the other clusters N = 5, 6, and 7) for which S(T) is cal-culated. - The curves of S T) for these systems are similar to those occurring with first-order phase transitions of macroscopic systems.Lindemann s criterion states that melting occurs for such systems when rms fluctuations reach 10%.For the small clusters studied, the rise in this function occurs at values of S slightly below 10%—an effect that can be attributed to the large ratio of surface to core atoms. 

Solidification First order phase transformation, in which a liquid (melt) crystallizes Sol-gel transition Transition of a colloidal solution into a solid network extending through the whole sample space. The network is made up of the colloidal particles attached to each other mechanically and might be bonded by various potentials. At the point of contact so-called necks establish. The sol-gel transition might be considered as exactly that point when a percolating net of particles (a cluster) spans through the wet fluid. See also gelation... 

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