Diluted Fe 3+ in silicate glasses: Structural effects of Fe-redox state and matrix composition. An optical absorption and X-band/Q-band EPR study

Vercamer, Vincent; Lelong, Gérald; Hijiya, Hiroyuki; Kondo, Yuki; Galoisy, Laurence; Calas, Georges

doi:10.1016/j.jnoncrysol.2015.08.010

Cited by 54 publications

(60 citation statements)

References 44 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Although these trends are conspicuous in our simulation data, a direct comparison with structure data obtained with silicate glasses is not fully satisfying because the glassy state can induce a structural reorganization around some cations (e.g. Benmore et al, 2010;Vercamer et al, 2015). Only a few studies, using in situ X-ray or neutron diffraction techniques, give some insights on the structure of silicate melts at liquidus temperature …”

Section: Accepted Manuscriptmentioning

confidence: 70%

Properties of magmatic liquids by molecular dynamics simulation: The example of a MORB melt

et al. 2017

View full text Add to dashboard Cite

International audienceA new atom-atom interaction potential is introduced for describing by classical molecular dynamics (MD) simulation the physical properties of natural silicate melts. The equation of state, the microscopic structure, the viscosity, the electrical conductivity, and the self-diffusion coefficients of ions in a mid-oceanic ridge basalt (MORB) melt are evaluated by MD over a large range of temperature and pressure (1673-3273 K and 0-60 GPa). A detailed comparison with experimental data shows that the model reproduces the thermodynamic, structural and transport properties of a MORB with an unprecedented accuracy. In particular, it is shown that the MORB melt crystallizes at lower mantle conditions into a perovskite phase whose the equation of state (EOS) is compatible with those proposed in the experimental literature. Moreover, in accordance with experimental findings, the simulation predicts not only that the MORB viscosity exhibits a (slight) minimum with the pressure, but also that the viscosity at high temperature remains very low (<100 mPa.s for T > 2273 K) even at high pressure (up to 40 GPa). However the evolution of the electrical conductivity with temperature and pressure is not always the symmetrical of that of the viscosity. In fact, the relationship between viscosity and electrical conductivity shows a crossover at around 2073 K

show abstract

Section: Accepted Manuscriptmentioning

confidence: 70%

Properties of magmatic liquids by molecular dynamics simulation: The example of a MORB melt

et al. 2017

View full text Add to dashboard Cite

show abstract

“…In the case of iron ions with M Fe2aO3 > ∼0.3 wt%, many measurements have been performed on the various types of glass fabricated under various processing conditions by using nonelement‐specific or element‐specific methods, including transmittance_ UV‐NIR measurements, X‐ray absorption fine structure (XAFS) pre‐edge (the lower energy region below the absorption edge) measurements, Mössbauer spectroscopy, neutron diffraction measurements, electron spin resonance (ESR) measurements, and nuclear magnetic resonance measurements . Some of these experimental results have not been able to be explained in terms of the commonly accepted understanding described above.…”

Section: Introductionmentioning

confidence: 99%

“…Some of these experimental results have not been able to be explained in terms of the commonly accepted understanding described above. This has led to many models having been proposed, including ones incorporating medium‐range structures around the iron ions or different/additional coordinations of iron ions . For example, they include combinations of three to five neighboring atoms around the target iron ion over the M Fe2O3 range between 0.3 and 4 wt%, such as clusters of Fe 3+ for M Fe2O3 of 1.5 wt% or higher, polymerization (clustering) with a five‐atoms combination of Fe 3+ with a 4‐coordination number of four (Fe 3+ ) with bridging oxygen (BO) to Si (Fe 3+ –BO–Fe 3+ –BO–Si), and an Fe–O–Fe structure with strong bonding .…”

Section: Introductionmentioning

confidence: 99%

“…On the other hand, the sensitivity and the element specificity of the commonly used measuring methods are poor for studying samples with lower concentrations (M Fe2O3 < ~0.1 wt%). Accordingly, there have been few reports on glass with M Fe2O3 < ~0.1 wt%.…”

Section: Introductionmentioning

confidence: 99%

“…Medium‐range structures around iron ions in glass depend on the base composition of the glass, the ratio of particular high‐active elements (Na, Ca, S, etc.) in the glass, and the parameters of glass processing, including melt‐temperature, pressure, surrounding gas atmosphere, and/or oxygen‐fugacity efficiency . The complex nature of glass containing hierarchical orders and voids has added to the confusion of this situation.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Vibrations and chemical states of iron ions in soda‐lime glasses determined by element‐specific X‐ray analyses

et al. 2018

View full text Add to dashboard Cite

We systematically study medium‐range structures including more than three neighboring atoms around iron ions (Fe2+ and Fe3+) in soda‐lime glass samples with low iron oxide concentrations (MFe2O3) and a wide number ratio of Fe2+ to all iron ions (Fe2+/ΣnFe). The precise medium‐range structures around iron ions in glass have not yet been revealed because of a lack of the appropriate measurement methods. To avoid this problem, we used element‐specific nuclear resonant inelastic scattering (NRIS) with synchrotron X‐rays to observe the vibrations of iron ions (57Fe). The vibrations are related to medium‐range structures with more than three neighboring atoms and to the potential asymmetry and the coordination environment, around iron ions. The NRIS method has high sensitivity and can measure over a wide concentration range. Linear combination fitting of the X‐ray absorption fine structure spectra, which measures only the first neighbors but is a faster than using the NRIS method, was also used additionally. A systematically produced set of glasses with 0.015–5 wt% MFe2O3 and 0–0.85 Fe2+/ΣnFe was measured with these methods. It was found that the soda‐lime glass possessed two different medium‐range structures with different iron ion valences (~2+ or ~3+), which were determined by the Fe2+/ΣnFe, and that these structures were generated during production of the glass. Moreover, these medium‐range structures were the same from 0.015 to 5 wt% MFe2O3.

show abstract

Effects of strong network modifiers on Fe3+/Fe2+ in silicate melts: an experimental study

Борисов

Behrens

Holtz

2017

Contrib Mineral Petrol

View full text Add to dashboard Cite

Diluted Fe 3+ in silicate glasses: Structural effects of Fe-redox state and matrix composition. An optical absorption and X-band/Q-band EPR study

Cited by 54 publications

References 44 publications

Properties of magmatic liquids by molecular dynamics simulation: The example of a MORB melt

Properties of magmatic liquids by molecular dynamics simulation: The example of a MORB melt

Vibrations and chemical states of iron ions in soda‐lime glasses determined by element‐specific X‐ray analyses

Effects of strong network modifiers on Fe3+/Fe2+ in silicate melts: an experimental study

Contact Info

Product

Resources

About