A Test of Angle Dispersive X-ray Diffraction of High-pressure Experiment at X17C

Jingzhu Hu¹, Zhong Zhong², Haozhe Liu³, Quanzhong Guo¹, Ho-kwang Mao¹

¹Geophysical Lab of Carnegie Institution of Washington

²NSLS of BNL

³University Stony Brook

jzhu@bnl.gov

NSLS-X17C (DAC)

We used a Sagittally bent Si monochromator to provide 30.4912 keV (0.40663 Angstrom) X-ray beam at X17C. Two crystals of 0.76 mm thick, with surface corresponding to the (001) planes, bent sagittally to 1 m radius, are used in the Laue mode.[1, 2] The bent Laue crystals provides high energy-resolution beam with a flux one order of magnitude greater than that of a perfect-crystal monochromator. K-B mirrors were used to focus the incident 200 x 200 micron beam down to 80 x 70 micron. CeO₂ was used to calibrate the sample to image plate distance. NaMgF₃ sample was tested in a diamond cell at pressures up to 30 GPa. Exposure time of 1' to 6' for different pressures yielded satisfactory diffraction patterns. The test results demonstrate the possibility of ADXD at X17C.

[1] Z. Zhong, et. al., Cryst. A 59 (2003) 1-6

[2] Z. Zhong, et. al. J. Appl. Cryst., 34 (2001) 646-653