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Low-Temperature Crystal Structures of the Hard Core Square Shoulder Model.

ABSTRACT: In many cases, the stability of complex structures in colloidal systems is enhanced by a competition between different length scales. Inspired by recent experiments on nanoparticles coated with polymers, we use Monte Carlo simulations to explore the types of crystal structures that can form in a simple hard-core square shoulder model that explicitly incorporates two favored distances between the particles. To this end, we combine Monte Carlo-based crystal structure finding algorithms with free energies obtained using a mean-field cell theory approach, and draw phase diagrams for two different values of the square shoulder width as a function of the density and temperature. Moreover, we map out the zero-temperature phase diagram for a broad range of shoulder widths. Our results show the stability of a rich variety of crystal phases, such as body-centered orthogonal (BCO) lattices not previously considered for the square shoulder model.

SUBMITTER: Gabrielse A

PROVIDER: S-EPMC5706227 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature

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Low-Temperature Crystal Structures of the Hard Core Square Shoulder Model.

Gabriëlse Alexander A Löwen Hartmut H Smallenburg Frank F

Materials (Basel, Switzerland) 20171107 11

In many cases, the stability of complex structures in colloidal systems is enhanced by a competition between different length scales. Inspired by recent experiments on nanoparticles coated with polymers, we use Monte Carlo simulations to explore the types of crystal structures that can form in a simple hard-core square shoulder model that explicitly incorporates two favored distances between the particles. To this end, we combine Monte Carlo-based crystal structure finding algorithms with free e ...[more]

PMID: 29112168

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