Open AccessX-ray and {Gamma}-ray spectroscopy of solids under pressure. Annual technical progress report, November 1996--October 1997
Author(s) -
R. Ingalls
Publication year - 1997
Language(s) - English
Resource type - Reports
DOI - 10.2172/481899
Subject(s) - x ray absorption fine structure , extended x ray absorption fine structure , synchrotron , materials science , synchrotron radiation , absorption (acoustics) , boron , helium , x ray , spectroscopy , absorption spectroscopy , analytical chemistry (journal) , optics , chemistry , atomic physics , physics , composite material , nuclear physics , quantum mechanics , chromatography
This report describes our recent synchrotron x-ray absorption fine structure (XAFS) measurements on a number of systems that undergo pressure induced changes in local structure at high pressure. Our general technique is based upon a pressure cell which utilizes scintered boron carbide anvils, since diamond anvils generally produce Bragg glitches which spoil the high quality EXAFS necessary for precision structural measurements. Sample pressure is determined at the beam-line by measuring and analyzing, via XAFS, the compression of some cubic material contained within the sample chamber. Recently we have extended this work to 77 K using helium gas for the applied force, rather than hydraulic oil