CRYSTALLOGRAPHY UNDER EXTREME CONDITIONS

Heinz Schulz

Institut für Kristallographie, Universität München, Theresienstr. 41, D-80333 Munich, Germany,
E-mail: Heinz.Schulz@lrz.uni-muenchen.de

Keyword: high pressure, high temperature, microcrystal diffraction, time resolved diffraction

Experiments in crystallography depend on the efficiency of facilities and equipments or on newly developed tools. Such devices may open bounderies, so that crystallography can enter new fields for studying properties of crystaline material. Some examples for such modern developments will be treated in this talk. These are:

1. High pressure experiments with diamond anvil cells, which allow experiments up to several hundred GPa, this means at pressures higher than in center of the earth.
2. High temperature experiments above 2000K.
3. Combination of high pressure and high temperature experiments, by which phase boundaries can be studied, e.g. those which play an important role in the interior of the earth and of the planets.
4. Microcrystal diffraction with single crystals of volumes between 0.1 to 1 m³. Such crystals can now be handled and used for single crystal diffraction experiments. Their diffracted intensities are free of systematic errors. In such a way the very efficients single crystal methods can be applied to crystaline material, which up to now could only be investigated in the form of polycrystaline samples.
5. Time resolved diffraction experiments, which can be carried out already at nanoseconds.
   

The equipments neccessary for such experiments and results obtained are reviewed with emphasis on high pressure experiments.