Correlation among electronic polarisability, optical basicity, interaction parameter and XPS spectra of Bi2O3-B2O3 glasses

The average electronic polarisability of the oxide ion (α O2- ), optical basicity (Λ), Yamashita-Kurosawa's interaction parameter (A) and oxygen Is (O1s) binding energy in x-ray photoelectron spectroscopy (XPS) of xBi 2 O 3 . (100-x)B 2 O 3 glasses (x=0∼65) have been examined to check correlations among them and to clarify the electronic structure of the glasses and bonding character of Bi-O. Both α O2- and Λ increase gradually with increasing Bi 2 O 3 content, and large α O2- values over 2 A 3 and large Λ values over 0.9 are obtained in the glasses with high Bi 2 O 3 contents. The interaction parameter ranges from about 0.05 to 0.25 and decreases with increasing Bi 2 O 3 content. The Ols peak in XPS spectra consists of two components: the Ols peak with higher binding energies, O1s(1), is assigned to B-O-B bonds and that with lower binding energies, O1s(2), corresponds to Bi-O-B and Bi-O-Bi bonds. The O1s(1) binding energy decreases gradually with increasing Bi 2 O 3 content but the O1s(2) binding energy is almost constant suggesting that the ioniclcovalent character of Bi-O bonds does not change significantly with composition. Close correlations are observed among α O2- , Λ, A and mean O1s binding energy. Particularly, it has been found that O1s binding energy is a good measure of the optical basicity of Bi 2 O 3 -B 2 O 3 glasses and the interaction parameter gives good information about the electronic polarisability of oxide glasses as well as optical basicity. It is found that Bi-O bonds in Bi 2 O 3 -B 2 O 3 glasses are more ionic compared with Sb-O bonds in Sb 2 O 3 -B 2 O 3 glasses.