Application of Mössbauer Spectroscopy in Earth Sciences

Inorganic polymers made of fayalite slag: On the microstructure and behavior of Fe

“…The range of IS values of all components denotes the presence of only Fe 2+ high spin (S = 2) ions in this sample. The IS and QS values of component Q1 correspond well to those expected for crystalline fayalite . The ΔQS values for this component are the lowest observed in this set of spectra, suggesting that this component corresponds mainly to the fayalite crystals dispersed in the slag, which were already detected using XRD and EBSD.…”

“…The IS and QS values of component Q1 correspond well to those expected for crystalline fayalite. 40,41 The DQS values for this component are the lowest observed in this set of spectra, suggesting that this component corresponds mainly to the fayalite crystals dispersed in the slag, which were already detected using XRD and EBSD. Component Q2 acquires IS and QS values lower than those of component Q1, having moreover larger DQS values.…”

Using iron speciation in authigenic carbonates from hydrocarbon seeps to trace variable redox conditions

“…M€ ossbauer spectroscopy is among the most advanced methods to determine Fe species and their relative contents in iron-bearing materials, including Fe 3þ /Fe 2þ ratios (e.g. Medina et al, 2006;Peiffer et al, 2015;Ram et al, 1998;Vandenberghe and Grave, 2013;Zachara et al, 2004;Zhang et al, 2013;Zheng et al, 2010Zheng et al, , 2002. These parameters related to Fe contents and speciation are effective tools for the analysis of redox conditions (e.g.…”

“…Medina et al, 2006;Ram et al, 1998;Zachara et al, 2004;Zheng et al, 2010). Additionally, kaolinite and muscovite tend to contain little Fe (Vandenberghe and Grave, 2013). Thus, accessory siderite or possibly ankerite rather than clay minerals have apparently caused the M€ ossbauer patterns, reflecting abundant ferrous Fe.…”

Hydrothermal synthesis of nanostructured hybrids based on iron oxide and branched PEI polymers. Influence of high pressure on structure and morphology

“…However, at 78 K and 298 K (see Figs.13 and 14), all spectra consist of narrow central doublets with an average quadrupole splitting of about 0.77 mm/s, confirming the superparamagnetic behaviour of the goethite nanoparticles (the tentative fitting of the central doublet via two doublet components was done in order to simulate the expected distributed quadrupole splitting parameters in such fine clusters[37,38]. Estimating the blocking temperature as the temperature where the average hyperfine magnetic field decreases at half of its maximum value (e.g.…”