The Impact of Colloidal Surface-Anchoring on the Smectic A Phase.
Liquid-crystalline phases are known for their unique properties, i.e., the combination of fluidity and long-range orientational and/or positional order. The presence of a colloidal particle gives rise to perturbations of this order locally. These perturbations are the origin of intercolloidal forces driving the colloidal self-assembly in a directed manner. Hence, the understanding of these perturbations is the first step in understanding and controlling the self-assembly process. Here, we perform Monte Carlo simulations to investigate the perturbations of orientational and positional order in a smectic A phase caused by a spherical colloid. We model the host phase via an interaction potential that reproduces characteristic features of phase behavior, structure, dynamics, and elasticity [S. Püschel-Schlotthauer et al. J. Chem. Phys. 2016, 145, 164903]. For strong homeotropic anchoring conditions, we find a Saturn ring defect and an onion structure in the smectic A phase; the latter has never been reported for colloids so far. For strong planar anchoring conditions, we find Boojum defects that become elongated at low temperature, similar to what is observed in experiments. However, for weak planar anchoring conditions, a double surface ring defect is exhibited in the smectic A phase.
Stranski-Laboratorium für Physikalische und Theoretische Chemie, Fakultät für Mathematik und Naturwissenschaften, Technische Universität Berlin , Straße des 17. Juni 135, 10623 Berlin, Germany.
Sergej
S
Püschel-Schlotthauer
Max Planck Institute for Dynamics and Self-Organization (MPIDS) , Am Faßberg 17, 37077 Göttingen, Germany.
Victor
V
Meiwes Turrión
Department of Chemical and Biomolecular Engineering, North Carolina State University , Engineering Building I, Box 7905, 911 Partners Way, Raleigh, North Carolina 27695, United States.
Carol K
CK
Hall
Max Planck Institute for Dynamics and Self-Organization (MPIDS) , Am Faßberg 17, 37077 Göttingen, Germany.
Marco G
MG
Mazza
Stranski-Laboratorium für Physikalische und Theoretische Chemie, Fakultät für Mathematik und Naturwissenschaften, Technische Universität Berlin , Straße des 17. Juni 135, 10623 Berlin, Germany.|Department of Chemical and Biomolecular Engineering, North Carolina State University , Engineering Building I, Box 7905, 911 Partners Way, Raleigh, North Carolina 27695, United States.
Martin
M
Schoen