Chinese Acad Sci, Inst High Energy Phys, Beijing Synchrotron Radiat Facil, Beijing 100039, Peoples R China
; Ist Nazl Fis Nucl, Lab Nazl Frascati, I-00044 Frascati, Italy
; Univ Bayreuth, Bayer Geoinst, D-95440 Bayreuth, Germany
; Univ Camerino, Dipartimento Sci Terra, I-62032 Camerino, MC, Italy
; Univ Camerino, INFM, I-62032 Camerino, MC, Italy
Article; Proceedings Paper
The O K-edge spectra of perovskites XTiO3 with X=Ca, Sr and Ba have been measured using electron energy-loss spectroscopy (EELS) and are analyzed using the ab initio full multiple-scattering (MS) calculations. The near-edge structures arise mainly from covalency by direct and/or indirect interaction between oxygen and metal. The coordination number of the cation and the site symmetry also influence the spectral shape and structures. Comparison of full MS simulations of different clusters around the excited atom allows to interpret and correlate the features present in the spectra of each compound to its specific atomic arrangement and electronic structure.