Polymers on the face-centered cubic lattice

First insights to freezing and coiiapse of fiexibie poiymers 

The expectation that the 19-mer, which can form a perfect shape without any holes ( 6-7-6 stmcture), is a prototype of peculiar behavior is, however, wrong. This is due to the existence of degenerate less symmetric ground-state conformations [as the exemplary conformation shown in Fig. 5.6(c)]. 

The described geometric peculiarities are, however, only properties of very short chains. One of the largest of the small chains that still possesses a nonspherical ground state is the 27-mer with the ground-state conformation shown in Fig. 5.6(d). For larger systems, the relative importance of the interior monomers will increase, because of the larger number of possible contacts. This requires the number of surface monomers to be as small as possible, which results in compact, sphere-like shapes. A representative example is the 30-mer shown in Fig. 5.6(e). 

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