THE KIEL-BERLIN-CELL: NEW DEVELOPMENTS AND RESULTS. W. Depmeier^l, K. Knorr², B. Annighöfer^{1, 1}Institute for Mineralogy, University of Kiel, Kiel, Germany; ²BENSC, Hahn-Meitner-Institute, Berlin, Germany

High pressure - high temperature crystal structure investigations play an important role in various fields of solid state sciences, including geosciences and studies of phase transitions. In the last few years we. have constructed a treatable high pressure cell of the piston-cylinder type for neutron powder diffractometry. This "Kiel-Berlin-Cell" runs successfully at the BERII reactor of BENSC, Hahn-Meitner-Institute, Berlin. Actual operating data are simultaneously 600 K and 17 kbar with a sample volume of 500 mm³. The zero-scattering Ti - Zr alloy used for the pressure cylinder allows Rietveld-refineable diffractograms to be collected. Some recent results will be reported and discussed.

In order to extend the accessible range of temperatures and pressures a new cell has been designed. We hope to attain at least 35 kbar and 773 K with this new "Kiel-Berlin-Cell II". The cell is currently being built.