Topological Defects in Size-Dispersed Solids

M. Reza Sadr-Lahijany; Purusattam Ray; H. E. Stanley

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arXiv · cond-mat/0003108

Topological Defects in Size-Dispersed Solids

M. Reza Sadr-Lahijany·Purusattam Ray·H. E. Stanley

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Abstract

We study the behavior of the topological defects in the inherent structures of a two-dimensional binary Lennard-Jones system as the size dispersity varies. We find that topological defects arising from the particle size dispersity are responsible for destabilizing the solid as follows: (i) for particle density $ρ\leq 0.9$, the solid melts through intermediate states of decreasing hexatic order arising from the proliferation of unbounded dislocations, (ii) for $ρ> 0.9$, the dislocations form grain boundaries, dividing the system into micro-crystallites and destroying the translational and orientational order.

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M. Reza Sadr-Lahijany, Purusattam Ray, H. E. Stanley. 2000-03-07. Topological Defects in Size-Dispersed Solids. https://arxiv.org/abs/cond-mat/0003108

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