Entropy Driven Ostwald's Stage Rule and Ripening in Polymer Crystallization

We present results on the spontaneous crystallization of a very extensive system (54 chains of 1000 hard sphere monomers) by means of a suite of Monte Carlo (MC) moves. Starting from an isotropic amorphous melt the system reaches a final crystalline state of unprecented perfection. We use the wealth of information gleaned from this simulation to assess the applicability of two classical crystallization paradigms introduced by Ostwald more than 100 years ago. In spite of the lack of dynamic information, the sequence of microstates joining the initially amorphous system with the final, stable face centered cubic chain crystal satisfactorily complies with both Ostwald's ripening and step rule. Given that there is neither non-bonded interaction (beyond the hard-sphere core) nor bending or torsion potentials in the polymer chains, our results strongly indicate that Ostwald's step rule and ripening can be purely entropy-driven.

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