English

Low-temperature crystal structures of the hard core square shoulder model

Soft Condensed Matter 2017-11-08 v1

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 which 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.

Keywords

Cite

@article{arxiv.1711.01103,
  title  = {Low-temperature crystal structures of the hard core square shoulder model},
  author = {Alexander Gabriëlse and Hartmut Löwen and Frank Smallenburg},
  journal= {arXiv preprint arXiv:1711.01103},
  year   = {2017}
}

Comments

Accepted in Materials

R2 v1 2026-06-22T22:35:09.331Z