OPTICAL ABSORPTION EDGE AND TRANSITION STUDIES OF
BISMUTH PHOSPHATE (Bi2O3)X(P2O5)1-X GLASSES
Sheik Azrif Bux Sheik Azmi Bux, Sidek Hj. Abdul Aziz,
Zainal Abidin Talib, & W. Mohd. Daud W. Yusoff
Ultrasonic and Glass Research Laboratory, Physics Department
Faculty of Science and Environmental Studies
Glasses with composition xBi2O3.(1-x)P2O5 were prepared over the range 0.05 ≤ x ≤ 0.23 by a single step process of Bi2O3 and P2O5. The amorphous nature of the glass compositions was confirmed by x-ray powder diffraction (XRD) studies. The optical absorption was recorded at room temperature in a wavelength range of 200-800 nm using UV-Visible Spectrophotometer. The values of optical band gap (Eopt) have been evaluated and were found to depend on the glass composition. It gives a very good fit for indicating indirect transitions. Different Thermal Analysis (DTA) data were used to determine the glass transition temperatures of the glass and has been interpreted in terms on the role of alkaline oxide in the matrix.
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