Obtaining Soft X-ray Emission and Absorption Spectra using SR from the VEPP-4 storage ring on the metrology station "Cosmos"
- Mr. Evgeniy KOROTAEV
- Mr. Evgeniy KOROTAEV (Nikolaev Institute of Inorganic Chemistry of the Siberian Branch of the Russian Academy of Sciences)
X-ray spectroscopy is powerful tool for investigation of the electronic structure of functional materials. X-ray emission spectra (XES) corresponding transition from valence orbitals to core levels allows to obtain information about atomic partial densities of occupied states of the elements in complex chemical compounds. X-ray absorption near edge structure (XANES) allows to study atomic partial densities of unoccupied states. Usage of synchrotron radiation for obtaining XES and XANES spectra is to essentially increase quality of experimental data. The experimental equipment of the "Cosmos"- synchrotron station was adjusted for obtaining soft XES-spectra of reference samples (quartz glass, aluminum and copper foils). In the present work were used two different optic schemes: flat (Bragg-scheme) and cylindrically bent crystals (Iogan’s scheme). Using the cylindrically bent crystal geometry has shown best result in obtaining soft XES-spectra. Also it was a special interest to obtain soft X-ray absorption spectra. For obtaining such spectra the double crystal scheme was used. Thus fine structure of soft X-ray absorption spectra was recorded for reference samples (aluminum, copper foils). Experimental XES and XANES spectra were compared with the spectra obtained on a laboratory X-ray spectrometer and the results of the quantum-chemical calculations. The authors are grateful to prof. L.N. Mazalov for useful discussions of experimental data.