Free Energy Landscape of Colloidal Clusters in Spherical Confinement

Beitrag in einer Fachzeitschrift
(Originalarbeit)


Details zur Publikation

Autorinnen und Autoren: Wang J, Mbah Chrameh F, Przybilla T, Englisch S, Spiecker E, Engel M, Vogel N
Zeitschrift: Acs Nano
Jahr der Veröffentlichung: 2019
ISSN: 1936-0851
Sprache: Englisch


Abstract



The structure of
finite
self-assembling systems depends
sensitively on the number of constituent
building blocks. Recently, it was demonstrated that hard sphere-like colloidal particles show a
magic number effect when confined in emulsion
droplets. Geometric con-struction
rules permit a few dozen magic numbers that
correspond to a discrete series of completely
filled concentric icosahedral shells. Here, we
investigate the free energy
landscape of these colloidal clusters as a
function of the number of their constituent building blocks for system sizes up to several thousand
particles. We find that minima in the free energy landscape,
arising from the presence of filled,
concentric shells, are significantly broadened, compared to their atomic
analogues. Colloidal clusters in spherical confinement can flexibly
accommodate excess particles by
ordering icosahedrally in the cluster center while changing the structure near
the cluster surface. In between
these magic number regions, the building blocks cannot arrange into filled
shells. Instead, we observe that defects
accumulate in a single wedge and therefore only affect a few
tetrahedral grains of the cluster. We predict the existence of this wedge by simulation and confirm its presence in
experiment using electron tomography. The introduction of the wedge minimizes the free energy penalty by
confining
defects to small regions within the cluster. In addition, the remaining ordered tetrahedral grains can
relax internal strain by breaking icosahedral symmetry. Our findings demonstrate how multiple defect mechanisms
collude to form the complex free energy landscape of colloidal clusters.


FAU-Autorinnen und Autoren / FAU-Herausgeberinnen und Herausgeber

Engel, Michael Prof. Dr.
Juniorprofessur für Modellierung von Selbstorganisationsprozessen
Englisch, Silvan
Lehrstuhl für Werkstoffwissenschaften (Mikro- und Nanostrukturforschung)
Mbah Chrameh, Fru
Juniorprofessur für Modellierung von Selbstorganisationsprozessen
Przybilla, Thomas
Lehrstuhl für Werkstoffwissenschaften (Mikro- und Nanostrukturforschung)
Spiecker, Erdmann Prof. Dr.
Lehrstuhl für Werkstoffwissenschaften (Mikro- und Nanostrukturforschung)
Vogel, Nicolas Prof. Dr.
Professur für Partikelsynthese
Wang, Junwei
Lehrstuhl für Feststoff- und Grenzflächenverfahrenstechnik


Zusätzliche Organisationseinheit(en)
Lehrstuhl für Werkstoffwissenschaften (Mikro- und Nanostrukturforschung)
Graduiertenkolleg 1896/2 In situ Mikroskopie mit Elektronen, Röntgenstrahlen und Rastersonden
Interdisziplinäres Zentrum, Center for Nanoanalysis and Electron Microscopy (CENEM)


Zitierweisen

APA:
Wang, J., Mbah Chrameh, F., Przybilla, T., Englisch, S., Spiecker, E., Engel, M., & Vogel, N. (2019). Free Energy Landscape of Colloidal Clusters in Spherical Confinement. Acs Nano. https://dx.doi.org/10.1021/acsnano.9b03039

MLA:
Wang, Junwei, et al. "Free Energy Landscape of Colloidal Clusters in Spherical Confinement." Acs Nano (2019).

BibTeX: 

Zuletzt aktualisiert 2019-22-07 um 11:28