0000000000053892
AUTHOR
Matthias Spengler
On the blue phase structure of hydrogen-bonded liquid crystals via 19F NMR
Abstract 19 F NMR spectra are simulated for blue phase I of FPHG( St 1.5 ∗ Ap 1.5 ) based on a model of a double-twisted substructure inside cylinders that form a body-centred cubic lattice. A kinetic matrix is included to describe jump processes over quarter pitch lengths. Though the lines in the NMR spectra are broad and featureless, changes in the widths and positions with temperature are well described by the blue phase model structure. The spectra in the chiral nematic N∗ phase are also simulated. Dynamics in the BP I are found to be slower than in the N∗ phase.
Photoresponsive Halogen-Bonded Liquid Crystals: The Role of Aromatic Fluorine Substitution
A new strategy for controlling the liquid crystalline and photophysical properties of supramolecular mesogens assembled via halogen bonding is reported. Changing the degree of fluorination at the halogen-bond donor of the supramolecular liquid crystal allows for the fine-tuning of the halogen bond strength and thereby provides control over the temperature range of the mesophase. At least three fluorine atoms have to be present to ensure efficient polarization of the halogen-bond donor and the formation of a mesophase. In addition, it was found that stilbazole acceptors are superior to their azopyridine counterparts in promoting stable liquid crystalline phases. The halogen-bond-driven supra…
Supramolecular Modification of ABC Triblock Terpolymers in Confinement Assembly
The self-assembly of AB diblock copolymers in three-dimensional (3D) soft confinement of nanoemulsions has recently become an attractive bottom up route to prepare colloids with controlled inner morphologies. In that regard, ABC triblock terpolymers show a more complex morphological behavior and could thus give access to extensive libraries of multicompartment microparticles. However, knowledge about their self-assembly in confinement is very limited thus far. Here, we investigated the confinement assembly of polystyrene-block-poly(4-vinylpyridine)-block-poly(tert-butyl methacrylate) (PS-b-P4VP-b-PT or SVT) triblock terpolymers in nanoemulsion droplets. Depending on the block weight fractio…
CCDC 1866422: Experimental Crystal Structure Determination
Related Article: Marco Saccone, Matthias Spengler, Michael Pfletscher, Kim Kuntze, Matti Virkki, Christoph Wölper, Robert Gehrke, Georg Jansen, Pierangelo Metrangolo, Arri Priimagi, Michael Giese|2019|Chem.Mater.|31|462|doi:10.1021/acs.chemmater.8b04197
CCDC 1866421: Experimental Crystal Structure Determination
Related Article: Marco Saccone, Matthias Spengler, Michael Pfletscher, Kim Kuntze, Matti Virkki, Christoph Wölper, Robert Gehrke, Georg Jansen, Pierangelo Metrangolo, Arri Priimagi, Michael Giese|2019|Chem.Mater.|31|462|doi:10.1021/acs.chemmater.8b04197
CCDC 1866420: Experimental Crystal Structure Determination
Related Article: Marco Saccone, Matthias Spengler, Michael Pfletscher, Kim Kuntze, Matti Virkki, Christoph Wölper, Robert Gehrke, Georg Jansen, Pierangelo Metrangolo, Arri Priimagi, Michael Giese|2019|Chem.Mater.|31|462|doi:10.1021/acs.chemmater.8b04197