Research Article
Optical Properties of Erbium Zinc Tellurite Glass System
Table 1
Composition (mol%), molar mass, molar volume, and  density of 
Er
2O
3-20ZnO-(
)TeO
2 glasses.
| | 
 |  | r2O3ā (mol%)
 | ZnO (mol%)
 | () TeO2ā
 (mol%)
 | Molar mass (g/mole)
 | Molar volume (cm3/mole)
 | Density (g/cm3)
 | Optical band gap (eV)
 |  | 
 |  | 0 | 20 | 80 | 139.62 | 33.08 | 4.22 | 3.04 |  | 1 | 20 | 79 | 141.68 | 33.05 | 4.28 | 3.10 |  | 2 | 20 | 78 | 143.36 | 32.86 | 4.36 | 3.12 |  | 3 | 20 | 77 | 144.28 | 32.75 | 4.44 | 3.13 |  | 4 | 20 | 76 | 146.26 | 32.66 | 4.47 | 3.14 |  | 
 | 
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