Roland Resel

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During the last years, self-assembled organic nanostructures have been recognized as a proper fundament for several electrical and optical applications. In particular, phenylenes deposited on muscovite mica have turned out to be an outstanding material combination. They tend to align parallel to each other forming needlelike structures. In that way, they(More)
We report on the epitaxial growth of periodic para-hexaphenyl (p-6P)/α-sexi-thiophene (6T) multilayer heterostructures on top of p-6P nanotemplates. By the chosen approach, 6T molecules are forced to align parallel to the p-6P template molecules, which yields highly polarized photoluminescence (PL)-emission of both species. The PL spectra show that the(More)
' INTRODUCTION Because of its high charge carrier mobility 1,2 and its ability to form well-ordered films, 3,4 pentacene (C 22 H 14), a highly conjugated oligoacene consisting of five benzene rings, has become the material of choice for the active layer in organic thin film transistors. Although pentacene (5A) is already used in commercially available(More)
The morphology and structure of 2,2′:6′,2″-ternaphthalene (NNN) deposited on muscovite mica(001) substrates was investigated by scanning force microscopy (SFM) and specular X-ray diffraction measurements. Consistently , both methods reveal the coexistence of needle-like structures with a {111} contact plane and {001} orientated island-like crystallites,(More)
The film growth of the conjugated organic molecule rubicene on silicon dioxide was studied in detail. Since no structural data of the condensed material were available, we first produced high quality single crystals from solution and determined the crystal structure. This high purity material was used to prepare ultrathin films under ultrahigh vacuum(More)
Nanoparticles capped with amine ligands with different steric properties, dodecylamine and oleylamine, respectively, are investigated in the solid state as well as in solution. A combined X-ray diffraction, small angle X-ray scattering and electron microscopy investigation showed that the nanoparticles exhibit the sphalerite modification of ZnS as crystal(More)
The scope of this work is the combination of the organic semiconductor pentacene (PEN) with different conjugated organic molecules to form application relevant heterostructures in vacuum sublimed films. Following a multi-technique approach – comprising x-ray diffraction, vibrational spec-troscopy, atomic force microscopy and photoelectron spectroscopy – PEN(More)
Dynamical scattering effects are observed in grazing-incidence X-ray diffraction experiments using an organic thin film of 2,2':6',2''-ternaphthalene grown on oxidized silicon as substrate. Here, a splitting of all Bragg peaks in the out-of-plane direction (z-direction) has been observed, the magnitude of which depends both on the incidence angle of the(More)
Amorphous films of the anticonvulsant drug carbamazepine are easily accessible by various methods, while the crystallization into specific polymorphs represents a challenging and time-consuming task. In this work, the crystallization of drop cast carbamazepine at silica surfaces is investigated by atomic force microscopy and both in situ and ex situ grazing(More)
The appearance of surface-induced phases of molecular crystals is a frequently observed phenomenon in organic electronics. However, despite their fundamental importance, the origin of such phases is not yet fully resolved. The organic molecule 6,6′-dibromoindigo (Tyrian purple) forms two polymorphs within thin films. At growth temperatures of 150 °C, the(More)