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G. Kahl:
"Inverse patchy colloids: structure, dynamics, and self-assembly from Monte Carlo simulations";
Talk: Ulam Computer Simulations Workshop, Lviv, Ukraine (invited); 06-21-2017 - 06-24-2017; in: "Challenges & Opportunities in Molecular Simulations", (2017), 23.

Anisotropy - be it in shape or in the interactions - has turned out to be an essential feature of colloidal particles that triggers their self-assembly strategies into mesoscopic target structures with desired properties. A relatively novel class of colloids that feature anisotropy in their interactions are colloidal particles whose surface is decorated by a heterogeneous charge distribution. As the particles are charged themselves, the interplay of attraction and repulsion between oppositely and likely charged surface regions guarantees that these colloids are able to form highly directional and, at the same time, strongly selective bonds with other particles. [is particular bonding mechanism is the reason why such particles are ideally suited to self-assemble into highly stable ordered structures which are otherwise inaccessible to conventional colloidal particles with surface decoration (commonly termed patchy particles) [1, 2]. [e fact
that, in addition, the diôerently charged regions are susceptible to external stimuli (such as electric ýelds) make such particles ideal building entities in targeted bottom-up assembly processes.
Quite a few theoretical models for such particles have been put forward in literature; this contribution will focus on Monte Carlo simulation based investigations on the physics of charged particles, decorated on their polar regions by oppositely charged patches. [ese colloids show an unexpected rich variety of self-assembly scenarios, which can be triggered by conýnement and/or external electric ýelds. One of the preferred ordered structures of these colloids are lamellar phases: they can emerge as hybrid crystal-liquid structures where transport of particles takes place through an otherwise stable layered structure [3].

1. E. Bianchi, C.N. Likos, and G. Kahl, ACS Nano 7, 4657 (2013).
2. E. Bianchi, C.N. Likos, and G. Kahl, Nano Letters 14, 3412 (2014).
3. S. Ferrari, E. Bianchi, and G. Kahl, Nanoscale (in press; 10.1039/C6NR07987C).

Anisotropy self-assembly mesoscopic structures colloids heterogeneous charge distribution

http://publik.tuwien.ac.at/files/publik_267014.pdf

Project Head Gerhard Kahl:
DFS