Liquid crystals - synthesis and properties
of mesogenic Ni(II) complexes
Katarzyna Purtaka,b, Adam Krówczyńskib, Ewa Góreckab
a
SKNCh „Fulleren”, Faculty of Chemistry,
University of Warsaw, Pasteura St. 1, 02-093 Warsaw
b
Faculty of Chemistry, Laboratory of Physicochemistry of Dielectrics and Magnetics,
University of Warsaw, Żwirki i Wigury St. 101, 02-089 Warsaw
kasia.purtak@gmail.com
New Ni(II) metallomesogens are described, having their chelating centre constructed
from two non-identical fragments: enaminoketone and barbiturylidenomethylenoamine
rings, thus low Cs symmetry. Various side chains were attached to the mesogenic core.
Despite a triangular molecular shape, almost all synthesised coupounds exhibit a liquid
crystalline hexagonal disordered columnar phase (Colh) with high clearing temperature.
The ability to create the columnar phase is propably connected with the permanent dipole
moment appearing in the non-symmetric molecules and dipole-dipole interactions between
molecules in columns. 1
Scheme 1. Synthesis of mesogenic Ni(II) complexes
Krówczynski, A.; Krzyczkowska, P.; Salamonczyk, M.; Górecka, E.; Pociecha, D.; Szydłowska, J.
"Mesogenic Ni(II) complexes of Cs symmetry forming Col h phase by dipole-dipole interaction",
Liquid Crystals,Vol.39(6), June 2012, 729-737
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