Reported here are the unique properties of N,N 0 ,N 00 -(3,4,5-tridodecyloxyphenyl)benzo[b,b 0 , b 00 ]tristhiophene-2,2 0 ,2 00 -tricarboxamide 3 as a new H-bonded discotic liquid crystal. Polarized optical microscopy and thermal analysis as well as variable temperature IR spectroscopy and X-ray diffraction confirm the presence of two thermotropic H-bonded hexagonal columnar mesophases that cover a temperature range from <-50 to 280 °C. Intermediate lyotropic mesophases of the highly viscous material aid the alignment of the hexagonal columnar mesophases, which is essential for a detailed structural characterization and applications. Solutions of 3 in heptane at concentrations as low as 1 wt % display isotropic organo-gel phases that consist of H-bonded networks of 3 but do not contain columnar stacks. 2D-X-ray diffraction studies on aligned samples of the thermotropic hexagonal columnar mesophases and DFT calculations on a tetramer of 3 reveal a helical columnar stacking of the individual benzotristhiophene units. Charge carrier mobility measured by time-resolved microwave conductivity is about 0.02 cm 2 V -1 s -1 in both hexagonal columnar mesophases and quasi temperature independent even across the phase transition between the two mesophases. The temperature independence is explained by the interrelation between stacking distance and mutual rotation because of the persistent intracolumnar H-bonds between amide groups. Half-life of the charge carriers, on the other hand, drastically increases in the low temperature hexagonal columnar mesophase, which is most likely a result of changing molecular dynamic and conformational states of the side chains. DFT calculations of the frontier orbitals show that the benzotristhiophene core is the sole contributor to the LUMO but does not contribute to the HOMO, whereas the trialkoxyaniline groups are the sole contributors to the HOMO. This suggests that the observed combined mobility is that of electrons alone because no hole transport is expected to occur between trialkoxyaniline groups that are spaced apart by more than 4 A ˚. Indeed, an electron mobility of 2 Â 10 -3 cm 2 V -1 s -1 but no transient signal for hole transport is obtained by timeof-flight charge carrier mobility measurements on a multi domain sample of 3.

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X-ray magnetic circular dichroism serves as a strong element-specific magnetic contrast mechanism in full-field transmission soft x-ray microscopy to image micromagnetic domain structures. A lateral resolution down to 25 nm is provided by Fresnel zone plates used as optical elements. Recording the images in varying external magnetic fields and the sensitivity to the direction of the magnetization allows for detailed studies of static magnetization reversal processes in magnetic thin films and nanopatterned elements. Results on highly magnetostrictive Terfenol-D layers are reported. The experimental findings of the switching processes in soft magnetic permalloy rectangular structures are consistent with micromagnetic simulations. The pulsed time structure of polarized synchrotron radiation allows for a stroboscopic imaging of spin dynamics on a sub-nanosecond timescale.

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