A multi-crystal spectrometer with a two-dimensional position-sensitive detector and contour maps of resonant Kβ emission in Mn compounds

A newly constructed multi-crystal X-ray spectrometer is described and its application to resonant inelastic X-ray scattering (RIXS) study on several Mn compounds are presented. The apparatus features a use of a two-dimensional position-sensitive proportional counter as well as five cylindrically bent rectangular Ge (440) crystals with 35 mm x 100 mm in size, whose radius of curvature is 550 mm. Diffracted X-rays from each crystal are horizontally dispersed and vertically focused onto different portion of the detector, and spectra are obtained by adding all the reflections from five crystals. Significant improvements in sensitivity have made it possible to present RIXS data as contour maps over wide energy ranges in both excitation and emission. RIXS contour maps for Kbeta emission from MnO, Mn2O3, MnO2, and KMnO4 are presented and their implications are discussed. In particular, it is stressed that near-resonant inelastic X-ray scattering process contributes significantly to fluorescence as well as fluorescence excitation spectra. (C) 2004 Elsevier B.V. All rights reserved.