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Formation of Polymorphic Cluster Phases for Purely Repulsive Soft Spheres

Bianca M. Mladek·Dieter Gottwald·Gerhard Kahl·Martin Neumann·Christos N. Likos
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Abstract

We present results from density functional theory and computer simulations that unambiguously predict the occurrence of first-order freezing transitions for a large class of ultrasoft model systems into cluster crystals. The clusters consist of fully overlapping particles and arise without the existence of attractive forces. The number of particles participating in a cluster scales linearly with density, therefore the crystals feature density-independent lattice constants. Clustering is accompanied by polymorphic bcc-fcc transitions, with fcc being the stable phase at high densities.

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Bianca M. Mladek, Dieter Gottwald, Gerhard Kahl, Martin Neumann, Christos N. Likos. 2005-11-07. Formation of Polymorphic Cluster Phases for Purely Repulsive Soft Spheres. https://doi.org/10.1103/physrevlett.97.019901

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