Physico-Chemical nanomaterials science
Induced optical properties of semiconductor nanocrystals soft assemblies
Parzyszek S., Lawera Z., Bagiński M., Wolska J. M., Pociecha D., Lewandowski W.
Faculty of Chemistry, University of Warsaw, Pasteura 1 St., 02-093 Warsaw, Poland. 
E-mail: sparzyszek@chem.uw.edu.pl

This work will aim to present liquid crystalline molecules as useful templates for assembling and modulating optical properties of semiconductor nanocrystals (NCs). Monodisperse, quasi-spherical InP/ZnS quantum dots and CdS small rods were synthesized and successfully functionalized with mesogenic ligands. Thermotropic organic coating of nanocrystals strongly defines distances to the nearest neighbor and influences optical properties. We have shown that functionalized NCs are able to form long-range ordered, reversibly reconfigurable structures in unary systems (achieving non-close packed symmetries) with the reversible shift of photoluminescence. 
In the next step, we introduced to our systems dimeric, bent-core molecules, forming helical nanofilaments. Due to the chemical compatibility of NCs’s organic coating and helical matrix, quasi-spherical and rod-like liquid crystalline NCs are attached to the helical matrix. We expect that achiral, fluorescent nanocrystals settled on helical nanofilaments will exhibit circularly polarized luminescence (CPL), and can be considered as a macroscopic scale source of CPL. Moreover, the CPL should be strongly enhanced for rod-like CdS.