Regensburg 2002 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Downloads | Hilfe
DF: Dielektrische Festkörper
DF 6: Poster
DF 6.7: Poster
Mittwoch, 13. März 2002, 14:30–18:00, Poster Chemie C
Determination of structural and physical properties of CuCl nanocrystals by comparison of SAXS experiments and exciton spectroscopy — •C. Popa1, S. Kriesen2, R. Kranold2, A. Hoell3, M. Haselhoff1, and H.-J. Weber1 — 1Universität Dortmund, Institut für Physik, 44221 Dortmund — 2Universität Rostock, Fachbereich Physik, Universitätsplatz 3, 18051 Rostock — 3Hahn-Meitner-Institut Berlin, Glienicker Str. 100, 14109 Berlin
Small angle x-ray scattering (SAXS) has been used to determine the mean radius R and the concentration x of CuCl nanocrystals embedded in a crystalline NaCl matrix as well as their critical radii as a function of nucleation temperature. The same properties have been determined by exciton spectroscopy (ES). Both experimental methods yield the same or at least very similar results for typical growth experiments, say R(t,T) and x(t,T). In contrast to reports on critical radii of CuCl nanocrystals in vitreous matrices we observe no hysteresis for nucleation and melting processes. There is only one significant difference shown by SAXS and ES: the optical radii of nanocrystals are smaller than the x-ray radii if R is near to one nanometer. The origin of this difference is studied in detail.