Measuring Chemical Shifts with Energy-Dispersive X-Ray Spectroscopy
Yueyun Chen1,2, Rebekah Jin1, Yarin Heffes1
1University of California, Department of Physics and Astronomy, Los Angeles, California 90095, USA.
Abstract:
Electron microscopy uses energy-dispersive x-ray spectroscopy (EDS) and electron energy loss spectroscopy (EELS) for elemental analysis. EDS and EELS energy resolutions are commonly between 30 and 100 eV or 0.01 and 1 eV, respectively. Large solid angle EDS detector technology has increased collection efficiency to enable precision spectroscopy via averaging of 0.02-0.1 eV. This improved precision gives access to chemical shifts; examples are shown in compounds of Al, Ti, and W. EDS can now detect chemical information in a complementary parameter space (accelerating voltage, thickness, atomic number) to that covered by EELS.
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