Mössbauer effect in inorganic glasses

Characterization and Conduction Mechanism of Highly Conductive Vanadate Glass

“…For example, a Tg vs. Δ plot for 20 BaO • 10 Fe2O3 • x WO3 • (70 -x) V2O5 glasses (x = 10 -50) yielded a slope of 680 K (mm s -1 ) -1 , [16] reflecting that Fe III atoms occupied only tetrahedral NWF sites. It means that they substituted V IV or V V atoms, [18,19] not octahedral W VI sites observed in tungstate glass. [21] Isomer shift (δ) provides chemical information like oxidation number, coordination number and electronic structure of the Mössbauer atoms.…”

“…[4] Mössbauer spectroscopy has become a very powerful tool for studying the local structure of oxide glass, since Mössbauer nuclides like 57 Fe and 119 Sn could be easily incorporated into oxide glasses as a probe. [ [5,13,16,[18][19][20][21] A slope of the straight line, obtained from the Tg vs. Δ plot, was 680 K (mm s -1 ) -1 when Fe III atoms occupied tetrahedral NWF sites. [18,19] However, the slope was 260 K (mm s -1 ) -1 when Fe III atoms occupied octahedral NWF sites, as in tungstate glass.…”

“…[ [5,13,16,[18][19][20][21] A slope of the straight line, obtained from the Tg vs. Δ plot, was 680 K (mm s -1 ) -1 when Fe III atoms occupied tetrahedral NWF sites. [18,19] However, the slope was 260 K (mm s -1 ) -1 when Fe III atoms occupied octahedral NWF sites, as in tungstate glass. [21] Significantly, the slope was only 35 K (mm s -1 ) -1 when Fe III atoms occupied NWM sites, as in phosphate glasses.…”

“…[21] Significantly, the slope was only 35 K (mm s -1 ) -1 when Fe III atoms occupied NWM sites, as in phosphate glasses. [18,19] A calibration plot of Tg vs. Δ was very useful when we characterized unknown glass samples because the structural role of Fe III atoms could be easily known. For example, a Tg vs. Δ plot for 20 BaO • 10 Fe2O3 • x WO3 • (70 -x) V2O5 glasses (x = 10 -50) yielded a slope of 680 K (mm s -1 ) -1 , [16] reflecting that Fe III atoms occupied only tetrahedral NWF sites.…”

“…The linewidth (Γ ) offers useful information on the uniformity of the structural units in the materials of interest, i.e., whether or not they are homogeneously distributed in the material or whether the material is crystalline or glassy. [18] Magnitude of Γ also gives information on the degree of crystallization of glass, i.e., estimation of the crystalline phase and particles precipitated in the glass matrix.…”