| Autor: |
Ştefan, RĂzvan, VinŢeler, Emil, Marcu, Alexandru, Taralunga, Goergeta, Popescu, Silvana, Bratu, Ioan |
| Předmět: |
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| Zdroj: |
Studia Universitatis Babes-Bolyai, Chemia; 2011, Vol. 56 Issue 1, p189-198, 10p, 1 Diagram, 2 Charts, 2 Graphs |
| Abstrakt: |
The vitreous system xFe2O3·(70-x)B2O3·15ZnO·15CaO with 0 ≤ x ≤ 25 mol% was prepared using the rapid melt quenching method. The effect of Fe2O3 on the borate glass structure was investigated by IR spectroscopy and illustrated by Density Functional Theory (DFT) method. The boron atoms are situated in trigonal [BO3] and tetragonal [BO4] groups and their ratio depends on Fe2O3 content. Two structural models were built, using DFT method, in agreement with IR experimental data, one for base glass 70B2O3·15ZnO·15CaO (x = 0 mol%) and another for the highest iron content in sample 25Fe2O3·45B2O3·15ZnO·15CaO (x = 25 mol%). Calculations with DFT method show that the addition of iron determinesthe breaking of B-O bonds in borate network and increases the number of [BO3] groups. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
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