|
NISCAIR ONLINE PERIODICALS REPOSITORY (NOPR) >
NISCAIR PUBLICATIONS >
Research Journals >
Indian Journal of Pure & Applied Physics (IJPAP) >
IJPAP Vol.43 [2005] >
IJPAP Vol.43(02) [February 2005] >
| Title: | Infrared study of the effect of P2O5 in the structure of lead silicate glasses |
| Authors: | Ahsan, M Rafiqul
Uddin, M Alfaz
Mortuza, M Golam |
| Keywords: | Infrared spectra
Lead silicate glasses
PbO-SiO2
Binary glass
P2O5 |
| Issue Date: | Feb-2005 |
| Publisher: | CSIR |
| IPC Code: | G01J 3/00 |
| Abstract: | The infrared spectra
of xPbO (1-x-z)SiO2zP2O5 glasses with a PbO:SiO2
molar ratio of 3:2 and z=0,1,2,5,30,40
and 50 mol% have been examined in the region 4000-400 cm-1, together with XRD. The structure of
PbO-SiO2 binary glass is significantly different from that of P2O5
substituted glasses. The low amount of P2O5 containing
PbO-SiO2 glasses results in infrared spectra of the same pattern as
3:2 binary lead silica glass but the maximum peak intensities and positions are
different. The spectra of high P2O5 (30-50 mol%)
containing glasses show an increased number of distinct peaks in the low
frequency region with a convolution of several broad Gaussians in the high
frequency region. All the spectra are base line corrected and deconvoluted to
appropriate number of Gaussians. The peaks and peak positions of the Gaussians
are assigned to Si-O-Si, Si-O-Pb, Si-O-P, P-O-P, O-P-O, P=O, P-O- etc. bonds. A variation in the band positions and the relative
amounts of bonds with P2O5 is also shown. The result indicates
that ortho- and pyro-phosphate are formed around 1-5 mol% P2O5
containing glasses and meta-phosphate
species from the high P2O5 containing glasses. The ionic
character of the phosphate groups P-O-, PO43- is well revealed by the formation of
new band within 1250-900 cm-1. The incorporation of high contents of P2O5
in the materials suggests that P5+ occupies the network position and
forms the linkage Si-O-P in the glasses. This Si-O-P bond may lead to the
formation of five and six coordinated silicon in the glass matrix. X-ray
diffraction pattern of the base samples, within the detection limit, shows that
all are homogeneous glasses and these have not shown any evidence of phase
separation on optical inspection. |
| Page(s): | 89-99 |
| ISSN: | 0975-1041 (Online); 0019-5596 (Print) |
| Source: | IJPAP Vol.43(02) [February 2005]
|
|
