Powder Diffractometer (POWGEN)

POWGEN secondary flight path

Secondary flight path for the Powder Diffractometer. The sample is 60 m from the moderator, necessitating a satellite building outside the Experiment Hall for the secondary flight path.

POWGEN is a flexible and versatile general purpose diffractometer useful for a wide range of structural studies. It can cover d-spacings from ~0.3 Å or less to 3 Å in a single measurement, and is capable of collecting typical Rietveld statistics in ~1 hour from a 1.0 cm3 sample with a < 0.2% resolution at short d-spacings and <1% resolution for nearly all d-spacings of interest. Alternatively, much of this resolution can be traded for intensity, making it possible to make measurements in < 15 minutes with still quite good resolution. The adjustable bandwidth-limiting choppers allow large variations in the incident wavelengths and pulse repetition rate. Insertable guide sections and the ability to trade resolution for intensity at the analysis stage allow users great latitude to optimize the data range, resolution, and statistical precision for each particular experiment.

POWGEN

Applications

Scientific studies at this instrument encompass a wide range of novel materials. These include, but are not limited to, structural studies of magnetic materials such as high-Tc superconductors, metal-insulator phase transitions, charge and orbital ordering transitions, and molecular magnets.

POWGEN

POWGEN pit.

Additional possibilities include nonmagnetic materials such as zeolite and aluminophosphate frameworks; metals and semiconductors; dielectrics, ferroelectrics, and thermoelectrics; and ab initio structure solutions of polycrystalline materials such as pharmaceutical compounds.

In addition, POWGEN is capable of acquiring refineable data sets in rapid data collection mode, making it an ideal instrument for parametric studies and time-resolved in situ studies of the electrochemistry of catalysts, ceramic membranes, hydrogen storage materials, and charging and discharging of battery materials.

POWGEN detector array

Detector array.