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X-ray absorption fine structure glasses containing Bi2O3 with third-order non-linearities

1997; Elsevier BV; Volume: 221; Issue: 2-3 Linguagem: Inglês

10.1016/s0022-3093(97)00417-1

1873-4812

Y. Shimizugawa, Naoki Sugimoto, Kimihiko Hirao,

X-ray Diffraction in Crystallography

Local structure around a bismuth ion in glasses containing Bi2O3 with third-order non-linearities were investigated by Bi LIII X-ray absorption fine structure (XAFS) and Bi 4f X-ray photostimulated spectrum (XPS). The chemical shifts of Bi LIII X-ray absorption near edge structure and Bi 4f XPS spectra of these glasses are similar to those of Bi2O5 rather than those of α-Bi2O3. They suggest that most of bismuth ions in glasses exist as Bi5+. The two-shell fitting analysis of Bi LIII extended X-ray absorption fine structure indicate the first neighbor Bi–O distances are by about 0.003 nm less than that in α-Bi2O3, and the second neighbor Bi–O distances are between 0.014 and 0.026 nm less. Total oxygen coordination number of bismuth in glasses are smaller than that in Bi2O5.