Troisiéme Conférence Européenne sur les Matériaux et les Procédés Avancés
J. Phys. IV France 03 (1993) C7-2129-C7-2136
Some application of synchrotron radiationH. FUESS
Technische Hochschule Darmstadt, Strukturforschung Petersenstrasse 20, 64287 Darmstadt, Germany
Continuous tuneable wavelength in the range [MATH], high brilliance and parallelity of the beam are the outstanding properties for all applications of synchrotron radiation in condensed matter research. High angular and time resolution in synchrotron X-ray diffraction may be achieved. Powder Diffraction pattern with a full width at half maximum (FWHM) of Bragg reflections of [MATH] display a resolution about five times better than laboratory equipment. Thus the investigation of structural phase transitions with only minor metric changes are feasible as well as direct determination of crystal structures from powder data. Registration of complete powder patterns in a few milliseconds opens the road to kinetic studies of crystallisation from glasses or melt and to structural phase transitions. The information from diffraction experiments which provide information on long range order is related to X-ray absorption experiments (XANES and EXAFS). X-ray absorption will provide information on the local environment of atoms (EXAFS) or on its electronic nature. Texture, strain and stress investigations with synchrotron radiation offer advantages as compared to laboratory X-ray work. The angular resolution is considerably improved due to the parallel beam geometry and the small beam size and the penetration depth may be varied by a factor of 6. Thus not only general orientation distribution functions but the anisotropy strain and complex stress behaviour at surfaces may be investigated in particular grains. Furthermore all kinds of surface studies at grazing incidence are performed with considerable advantage.
© EDP Sciences 1993