Berlin 2005 – wissenschaftliches Programm
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CPP: Chemische Physik und Polymerphysik
CPP 21: Nanoparticles
CPP 21.3: Vortrag
Dienstag, 8. März 2005, 10:15–10:30, TU C243
Structure determination of CdS nanoparticles using synchrotron radiation: New methods and results — •Franziska Niederdraenk1, Andreas Stahl1, Christian Kumpf1, Reinhard Neder2, and Eberhard Umbach1 — 1Experimentelle Physik II, Univ. Würzburg — 2Inst. für Mineralogie und Kristallstrukturlehre, Univ. Würzburg
Semiconductor nanoparticles are of increasing interest for both, applied and fundamental research. Besides applications in material science, they are used as markers in biology and for cancer treatment. Furthermore, 1-5 nm large particles are of particular interest in fundamental research since they represent a size scale between solid state and molecular physics.
However, a precise determination of geometrical parameters is difficult in this range. Potentially, diffraction methods are able to provide precise structural information, but common analysis methods do not yield precise results in the particle range below 5 nm. We present a new approach for the analysis of powder diffraction data obtained from small particles. The entire particle is modelled and its diffractogram is computed using the Debye formula. This allows us to address not only fundamental parameters like size and crystal structure, but also the shape, stress, relaxation effects, and stacking faults.