Phase Diagram and Structure Map of Binary Nanoparticle Superlattices from a Lennard-Jones Model

ORAL

Abstract

In this work, we show that a binary system interacting through Lennard-Jones (LJ) potential predicts all phases reported in experiments in which nanoparticles are effectively described as quasi hard spheres. Furthermore, we show that binary lattices may be described as combinations of a small number of particle clusters, motifs, which generalize the four Z-N that describe Frank Kasper phases. We report a phase diagram consisting of 53 equilibrium phases, whose stability is quite insensitive to the microscopic details of the potentials, thus giving raise to some universality. Our results show that meta-stable phases share the same motifs as equilibrium phases. Connections with packing models, phase diagrams with repulsive potentials and the prediction of new superlattices in experiments are thoroughly discussed.

*Work at Ames Laboratory was supported by the US Department of Energy, Basic Energy Sciences, Materials Science and Engineering Division, under Contract No. DE-AC02-07CH11358, including a grant of computer time at the National Energy Research Supercomputing Center (NERSC) in Berkeley, CA. The Laboratory Directed Research and Development (LDRD) program of Ames Laboratory supported the use of GPU-accelerated computing.

Presenters

  • Shang Ren

    • Department of Physics and Astronomy, Rutgers University

Authors

  • Shang Ren

    • Department of Physics and Astronomy, Rutgers University
  • Yang Sun

    • Ames Laboratory
  • Feng Zhang

    • Ames Lab
    • Ames Laboratory
    • Ames Laboratory and Department of Physics and Astronomy, Iowa State University
  • Alex Travesset

    • Iowa State University
    • Ames Lab
    • Department of Physics and Astronomy, Iowa State University
    • Physics and Astronomy, Iowa State University and Ames Lab
    • Ames Laboratory, Iowa State University
  • Cai-Zhuang Wang

    • Ames Laboratory
    • Ames Laboratory and Department of Physics and Astronomy, Iowa State University
    • Department of Physics and Astronomy, Iowa State University
    • Department of Physics and Astronomy, Iowa State University/Ames Laboratory
  • Kai-Ming Ho

    • Iowa State University
    • Ames Laboratory and Department of Physics and Astronomy, Iowa State University
    • Department of Physics and Astronomy, Iowa State University
    • Department of Physics and Astronomy, Iowa State University/Ames Laboratory