電子線プローブマイクロアナライザー(EPMA)によるFe^<2+>/Fe^<3+>値マッピング Fe^<2+>/Fe^<3+> Mapping with an Electron Probe Microanalyzer (EPMA)
The relative intensities of Fe Lα<SUB>1, 2</SUB> and Lβ<SUB>1</SUB> X-ray emission peaks differ significantly with valance state and bond association. These X-ray emission peaks cannot be distinguished from each other using an energy-dispersive spectrometer (EDS), because the difference in energy between these peaks is smaller than the spectral resolution of EDS (approximately 100-150 eV). However, these emission peaks can be distinguished from each other using a wavelength-dispersive spectrometer (WDS). A crystal whose 2d value is about 60 A is considered to be suitable for analyzing the first order of Fe Lα<SUB>1, 2</SUB> and L β<SUB>1</SUB> X-ray emission peaks. The second order of these peaks can also be analyzed using lead stearate (STE : 2d=100.4 Å) crystal. Although it is difficult to use the ' peak seek' routine for a mapping analysis, the effects of chemical shifts can be suppressed by configuring the spectrometer. The interferences of high orders of Si and Na emission peaks can be suppressed by a pulse height analysis. Applying a mapping technique to measuring Fe Lα <SUB>1, 2</SUB> and Lβ<SUB>1</SUB> emission peaks, Fe<SUP>2+</SUP>/Fe<SUP>3+</SUP> mapping can be obtained using an electron probe microanalyzer.
地學雜誌 108(2), 122-131, 1999-04-25
Tokyo Geographical Society