Regensburg 2007 – scientific programme
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MM: Fachverband Metall- und Materialphysik
MM 20: Poster session
MM 20.49: Poster
Tuesday, March 27, 2007, 14:45–18:00, Poster C
119Sn Mössbauer Spectroscopy of tin containing float glass — •Verena Jung1, Ksenofontov Vadim1, Claudia Felser1, Maria Luisa Aigner2, Thomas Pfeiffer2, and Dirk Sprenger2 — 1Johannes Gutenberg - Universität, 55099 Mainz, Germany — 2Schott AG, 55122 Mainz, Germany
According to the production process of float glasses tin is used as a common refining agent. Since the surface quality of the glass strongly depends on the local distribution of Sn-redox states, the influence of process parameters on Sn2+/Sn4+ ratios and the assignment to their structural role in the glass network is extremely helpful. Therefore, glass compositions based on SiO2-Al2O3-B2O3-CaO-SnO2 were molten with additions of 0,1, 0,3 and 0,5 wt% SnO2. All samples were tempered for 7 days at 1400oC in N2 and N2-air mixtures with controlled pO2-values of 10−2 and 10−5 bar, respectively. Hyperfine parameters for the tin nucleus in different structural units and their oxidation states were calculated from 119Sn Mössbauer spectra, using theoretical simulations of electron densities and electric field gradients with the Wien2k software. Finally, the thermochemical impact of oxygen on the structure of Sn-bearing glasses is discussed.