FTIR studies of BPO4 center dot 2SiO(2), BPO4 center dot SiO2 and 2BPO(4)center dot SiO2 joints in amorphous and crystalline forms

The MIR spectra of glasses and devitrificates of BPO4. 2SiO(2), BPO4 SiO2 a nd 2BPO(4). SiO2 compositions have been shown. The bands arising from the S i-O, B-O and P-O bonds vibrations can be assigned in the spectra of the abo ve samples. All bands appear almost at the same wavenumber range: what caus es their coincidence? Therefore, all spectra of crystalline and amorphous m aterials were decomposed into component bands. The decomposed MIR spectra o f these samples, as well as the tetragonal boron orthophosphate BPO4 and th e low temperature crystobalite spectra, were then compared. Therefore, one can estimate the probability of the existence of any compounds within the B PO4-SiO2 (P2O5-B2O3-SiO2) system. The presence of BPO4. 2SiO(2) was reporte d in a few papers. The results obtained in this work can be treated as an a ttempt to verify the above hypothesis verifying because of the opposed info rmation existing on this subject in literature. (C) 1999 Elsevier Science B .V. All rights reserved.