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arXiv · 0910.2103

Ionic mixtures in two dimensions: from crystals to chain and dipole gases

Lahcen Assoud·René Messina·Hartmut Löwen
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Abstract

The ground state of a two-dimensional ionic mixture composed of oppositely charged spheres is determined as a function of the size asymmetry by using a penalty method. The cascade of stable structures includes square, triangular and rhombic crystals as well as a dipolar pair gas and a gas of one-dimensional crystalline chains. Thereby we confirm the square structure, found experimentally on charged granulates, and predict new phases detectable in experiments on granular and colloidal matter.

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Lahcen Assoud, René Messina, Hartmut Löwen. 2009-10-12. Ionic mixtures in two dimensions: from crystals to chain and dipole gases. https://arxiv.org/abs/0910.2103

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