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Title: Disorder and demixing in bidisperse particle systems assembling bcc crystals
Colloidal and nanoparticle self-assembly enables the creation of ordered structures with a variety of electronic and photonic functionalities. The outcomes of the self-assembly processes used to synthesize such structures, however, strongly depend on the uniformity of the individual nanoparticles. Here, we explore the simplest form of particle size dispersity—bidispersity—and its impact on the self-assembly process. We investigate the robustness of self-assembling bcc-type crystals via isotropic interaction potentials in binary systems with increasingly disparate particle sizes by determining their terminal size ratio—the most extreme size ratio at which a mixed binary bcc crystal forms. Our findings show that two-well pair potentials produce bcc crystals that are more robust with respect to particle size ratio than one-well pair potentials. This suggests that an improved self-assembly process is accomplished with a second attractive length scale encoded in the particle–particle interaction, which stabilizes the second-nearest neighbor shell. In addition, we document qualitative differences in the process of ordering and disordering: in bidisperse systems of particles interacting via one-well potentials, we observe a breakdown of order prior to demixing, while in systems interacting via two-well potentials, demixing occurs first and bcc continues to form in parts of the droplet down to low size ratios.  more » « less
Award ID(s):
2144094
PAR ID:
10573454
Author(s) / Creator(s):
; ; ; ;
Publisher / Repository:
AIP Publishing
Date Published:
Journal Name:
The Journal of Chemical Physics
Volume:
161
Issue:
5
ISSN:
0021-9606
Page Range / eLocation ID:
054715
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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