ブックタイトル日本結晶学会誌Vol61No3

概要

日本結晶学会誌Vol61No3

Changyong PARK, Arun S. BOMMANNAVAR, Paul CHOW, Richard A. FERRY, Rostislav HRUBIAK, Curtis KENNEY-BENSON, Yue MENG,Dmitry POPOV, Eric ROD, Guoyin SHEN, Jesse S. SMITH, Maddury S. SOMAYAZULU, Nenad VELISAVLJEVIC, Yuming XIAOFig.1 HPCAT beamlines and the four experimental hutches independently running with dedicated techniques.Fig.2 A photo showing a poly-capillary focusing optics（label 2）extending into a diamond anvil cell（label 1）on scatteringside; and a comparison between the raw data collected using conventional post-sample slits and the spectrum afterremoval of the parasitic scatterings（adapted from Ref.6）.research, probing phonon dynamics, charge dynamics,and electronic and spin states, using X-ray spectroscopytechniques including X-ray emission spectroscopy（XES）,inelastic X-ray scattering（IXS）, and nuclear resonancescattering（NRS）, all of which are optimized for diamondanvil cell. The beamline uses scannable monochromaticX-rays in the range 4.5～38 keV, a seventeen-elementanalyzer array for IXS, and a poly-capillary half-lens forXES. 5）These techniques commonly require high incidentflux and large collection solid angles. Depending on theexperimental requirement, the focused beam size is choseneither 30（V）×50（H）μm 2 for higher flux or reduced to 3（V）×5（H）μm 2 for smaller sample size at the cost of theincident flux. For the double-differential cross-section ofIXS reduces the scattered intensities by several orders ofmagnitude compared to the incident flux, the signal-to-noiseratio becomes often the most significant challenge, especially,for the parasitic scattering from surrounding materials,e.g., diamonds, gasket, pressure transmitting medium, andpressure markers included in the diamond anvil cell togetherwith sample. The spectrometer is equipped with a polycapillaryfocusing optics on the scattering side to reduce theparasitic scatterings and improve the signal-to-noise ratio（Fig.2）.6）Together with high-pressure X-ray diffraction（XRD）, the high-pressure spectroscopy techniqueshave been crucial to reveal materials state under extremeconditions, e.g., chemistry of iron-oxides under deep-Earthconditions. 7）3．16-ID-B：High-performance high-pressurediffraction beamlineX-ray diffraction（powder and single crystal）is the mostwidely used techniques for studying material properties athigh pressures with diamond anvil cells（DACs）. It provides164日本結晶学会誌第61巻第3号（2019）