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arXiv · 0709.2035

Coexistence of hexatic and isotropic phases in two-dimensional Yukawa systems

Wei-Kai Qi·Shao-Meng Qin·Xiao-Ying Zhao·Yong Chen
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Abstract

We have performed Brownian dynamics simulations on melting of two-dimensional colloidal crystal in which particles interact with Yukawa potential. The pair correlation function and bond-orientational correlation function was calculated in the Yukawa system. An algebraic decay of the bond orientational correlation function was observed. By ruling out the coexistence region, only a unstable hexatic phase was found in the Yukawa systems. But our work shows that the melting of the Yukawa systems is a two-stage melting not consist with the KTHNY theory and the isotropic liquid and the hexatic phase coexistence region was found. Also we have studied point defects in two-dimensional Yukawa systems.

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Wei-Kai Qi, Shao-Meng Qin, Xiao-Ying Zhao, Yong Chen. 2008-09-03. Coexistence of hexatic and isotropic phases in two-dimensional Yukawa systems. https://doi.org/10.1088/0953-8984%2F20%2F24%2F245102

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