A novel mesoporous MCM-41-type of hybrid material was synthesized by co-condensation of tetraethyl orthosilicate and the chelate ligand (3-trimethoxysilylpropyl)[3-(2-pyridyl)-1pyrazolyl]acetamide (1) in the presence of cetyltrimethylammonium bromide as template. Surfactant extraction produced hybrid mesoporous materials with uniform mesoscale channels, large pore volumes, and high specific surface areas. The preservation of the chelate ligand structure during the hydrothermal synthesis and the acid extraction process was confirmed by 13 C CP-MAS NMR spectroscopy. Solid epoxidation catalysts can be obtained by introducing oxodiperoxomolybdenum species MoO(O 2 ) 2 into the hybrid materials via a ligand exchange reaction. All molybdenum-containing catalysts showed high activity for the liquid-phase epoxidation of cyclooctene with t BuOOH and stability against leaching of active molybdenum species. The excellent stability of these catalysts indicated that almost all the incorporated chelate ligands are chemically accessible for the coordination of the catalytically active MoO(O 2 ) 2 moieties.

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The X‐ray diffraction method was tested for the investigation of the structure of thin fluorocarbon films grown in a glow discharge in tetrafluoroethylene. It could be shown that the computed electron densities are strongly related to the structure of the well known linear molecule of polytetrafluoroethylene. The results are supported by infrared absorption spectra. Foreign atoms and chain branching being a reason for the amorphous structure of the films were ascertained.

A pulsed mid-frequency magnetron sputtering technique was used to deposit MgO films. Atomic force microscopy, Rutherford backscattering, x-ray diffraction, and a diode discharge device were used to characterize surface morphology, oxygen content, crystalline structure, and the secondary electron emission (γ) coefficient of the films, respectively. The oxygen content (56 at. %) in all the films remained constant. However, surface morphology, crystalline structure, and the secondary electron emission properties of the films are strongly dependent on the O2 flow rate. As the O2 flow rate is increased from 3 to 10 sccm, a sudden decrease in the grain size and the γ coefficient of the films can be observed, and the crystalline orientation evolves from a strong (200) preferred orientation continuously to a fully (220) preferred orientation. Further increase of O2 flow rate results in a slight change in the grain size and the crystalline orientation, but a considerable increase in the full width at half maximum of the x-ray diffraction peaks and a significant decrease in the γ coefficient of the films. We found that preferred orientation and crystalline quality are the main factors that influence the secondary electron emission properties of the MgO films.

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