Abstract
The decomposition of fayalite (Fe2SiO4) in oxygen potential gradients is studied at T=1,418 K. The compound will be decomposed into its component oxides wüstite, Fe1−δO, and silica, SiO2, by the simultaneous action of two different oxygen partial pressures, exceeding a critical ratio, despite the fact that fayalite is stable at both the lower and the higher oxygen potential. A quantitative analysis of the decomposition process caused by defect fluxes within the bulk Fe2SiO4 is given.
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References
Borchardt G, Schmalzried H (1971) Silikatbildung im festen Zustand. Z Phys Chem NF 74:265–283
Brindley GW, Hayami R (1965) Kinetics and Mechanism of formation of forsterite (Mg2SiO4) by solid state reaction of MgO and SiO2. Phil Mag 12:505–514
Buening DK, Buseck PR (1973) Fe-Mg lattice diffusion in olivine. J Geophys Res 44:6852–6862
Darken LS, Gurry RW (1945) The system iron-oxygen I. The wüstite field and related equilibria. J Am Chem Soc 67:1398–1412
Duckwitz CA, Schmalzried H (1971) Reaktionen zwischen festen Oxiden unter Einschluß von Gastransport. Z Phys. Chem NF 76:173–193
Hallwig D, Schachtner R, Sockel G (1982) Diffusion of Magnesium, Silicon and Oxygen in Mg2SiO4 and formation of the compound in the solid state. In: Dyrek K, Haber J and Nowotny J (eds) Reactivity of Solids, Proceedings of the 9th International Symposium on the Reactivity of Solids, Elsevier Science Publishers, Amsterdam, pp 168–172
Hermeling J (1984) Eisentracerdiffusionskoeffizienten im Mischkristall (Fe x Mg1−x )2SiO4. Ph D Thesis, Universität Hannover: 66–68
Hermeling J, Schmalzried H (1984) Tracerdiffusion of Fecations in olivine (Fe x Mg1−x )2SiO4(III). Phys Chem Minerals 11:161–166
Lenz JG, Nicholson PS, Smeltzer WW (1977) Diffusion controlled reaction between β-quarz and magnesia. J Am Ceram Soc 60:370–371
Martin M, Schmalzried H (1985) Cobaltous oxide in an oxygen potential gradient: morphological stability of the phase boundaries. Ber Bunsenges Phys Chem 89:124–130
Nakamura A, Schmalzried H (1983) On the nonstoichiometry and point defects of olivine. Phys Chem Minerals 10:27–37
Nakamura A, Schmalzried H (1984) On the Fe2+-Mg2+-interdiffusion in olivine (II). Ber Bunsenges Phys. Chem 88:140–145
Reddy KPR, Oh SM, Major LD, Cooper AR (1980) Oxygen diffusion in forsterite. J Geophys Res 85:322–326
Schmalzried H (1965) Point defects in ternary ionic crystals. In: Progress in Solid State Chemistry 8:265–308
Schmalzried H (1978) Reactivity and point defects of double oxides with emphasis on simple silicates. Phys Chem Minerals 2:279–294
Schmalzried H, Laqua W, Lin PL (1979) Crystalline oxide solid solutions in oxygen potential gradients. Z Naturforsch 34a:192–199
Schmalzried H, Laqua W (1981) Multicomponent oxides in oxygen potential gradients. Ox Metals 15:339–353
Sockel HG (1974) Defect structure and electrical conductivity of crystalline ferrous silicate. In: Seltzer MS and Jaffee RI (eds) Defects and transport in oxides. Plenum, New York, pp 341–354
Windhager HJ, Borchardt G (1975) Tracerdiffusion und Fehlordnung in dem Orthosilikat Co2SiO4. Ber Bunsenges Phys Chem 79:1115–1119
Yamaguchi G, Tokuda T (1967) Some aspects of solid state reactions between oxides. Bull Soc Japan 40:843–851
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Brinkmann, U., Laqua, W. Decomposition of fayalite (Fe2SiO4) in an oxygen potential gradient at 1,418 K. Phys Chem Minerals 12, 283–290 (1985). https://doi.org/10.1007/BF00310341
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DOI: https://doi.org/10.1007/BF00310341