Abstract
A series of powdered and oriented single crystals of riebeckite-arfvedsonite have been examined with the Mössbauer technique above and below the magnetic ordering temperatures. Using fitted spectra that result in essentially similar quadrupole pairs, site occupancies were determined for 5 samples. Fitted spectra of oriented single crystals are associated with inequal pairs. The quadrupole splitting and isomer shifts are indistinguishable from those of the powdered samples. For the purpose of determining site occupancy paramagnetic spectra at L.N. temperatures appear to have little advantage over those obtained at room temperatures. The use of cryogenics to obtain magnetic hyperfine splitting increases experimental times several fold; however we conclude that in most cases the additional information and greater accuracy of Fe+2/Fe+3 warrants the additional effort.
Magnetic order detected at cryogenic temperatures has an overall antiferromagnetic character. The orientation of the magnetic moment for Fe+3 is not parallel to a principal crystallographic axis, and its orientation near 〈316〉 suggests that there is magnetic coupling between the cation ribbons containing the octahedrally coordinated iron. The magnetic behavior can be interpreted satisfactorily using the Ising model developed for two dimensional lattices and extended to loosely coupled chains.
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References
Anderson, E.B., Fenger, J., Rose-Hansen, J.: Determination of (Fe2+)/(Fe3+) - ratios in arfvedsonite by Mössbauer spectroscopy. Lithos 8, 237–246 (1975)
Bancroft, G.M: Mössbauer spectroscopy. New York: John Wiley & Son, Chapt. 8, 1973
Bancroft, G.M., Burns, R.G.: Mössbauer and absorption spectral study of alkali amphiboles. Mineral. Soc. Am. Spec. Pap. 2, 137 (1969)
Bancroft, G.M., Burns, R.G., Maddock, A.G.: Determination of cation distribution in the cummingtonite-grunertite series by Mössbauer spectra. Am. Mineral. 52, 1009–1026 (1967)
Bancroft, G.M., Burns, R.G., Stone, A.J.: Applications of the Mössbauer effect to silicate mineralogy - II. Iron silicates of unknown and complex crystal structures. Geochim. Cosmochim. Acta 32, 547–559 (1968)
Borg, I.Y.: Optical properties and cell parameters in the glaucophaneriebeckite series. Contrib. Mineral. Petrol. 15, 67–92 (1967)
Borg, R.J., Borg, I.Y.: Magnetic order in certain alkali amphiboles - A Mössbauer investigation. J. Phys. Paris, Suppl. No. 12, 35, C6-553–556 (1974)
Borg, R.J., Borg, I.Y.: The magnetic structure of an alkali amphibole (abstract). Cracow, Poland: Proc. Int. Conf. Mössbauer Spectroscopy 1, 1975, p. 167.2
Borg, R.J., Kitchens, T.A.: Magnetization of gold-iron alloys. J. Phys. Chem. Solids 34, 1323–1334 (1973)
Borg, R.J., Lai, D.Y., Borg, I.Y.: Use of magnetic hyperfine splitting to determine Fe+2/Fe+3 ratios in complex silicate minerals. Nature (Phys. Sci.) 246, 46–48 (1973)
Borg, R.J., Szofran, F.R., Burmester, W.L., Selmyer, D.J.: Magnetic ordering in several Fe-chain silicate compounds. Proceedings 20th Annual Conf. on Magnetism and Magnetic Materials 24, 365–368 (1974)
DeJongh, L.J., Miedema, A.R.: `Experiments on simple magnetic model systems, Adv. Phys. 23, (especially) 21–47 (1974)
Ernst, W.G., Wai, C.M.: Mössbauer, infrared, X-ray and optical study of cation ordering and dehydrogenation in natural and heat treated sodic amphiboles. Am. Mineral. 55, 1226 (1970)
Goldman, D.S., Rossman, George R.: The identification of Fe+2 in the M4 site of calcic amphiboles. Am. Mineral. 62, 205–216 (1977)
Hafner, S.S., Ghose, S.: Iron-magnesium distribution in cummingtonites (Fe, Mg)7 Si8O22(OH)2. Z. Kristallogr. 133, 301–326 (1971)
Keller, H., Kundig, W.: Mössbauer study of the two-dimensional antiferromagnet (CH3NH3)2 FeCl4. Crackow, Poland: Proc. Int. Conf. Mössbauer Spectroscopy 1975
Kramers, H.A., Wannier, G.H.: Statistics of the two dimensional ferromagnet, Part I & II. Phys. Rev. 60, 252–276 (1941)
Landau, L., Lifshitz, E.M.: Statistical physics. London: Pergamon Press 1958, p. 482
Law, A.D.: Critical evaluation of ‘Statistical Best Fits’ to Mössbauer spectra. Am. Mineral. 58, 128–131 (1973)
Montroll, E.W.: Statistical mechanics of nearest neighbor systems. J. Chem. Phys. 9, 706–721 (1941)
Seifert, F.: Compositional dependence of the hyperfine interaction of 57Fe in anthophyllite. Phys. Chem. Minerals. 1, 43–52 (1977)
Ungaretti, L., Mazzi, F., Rossi, G., Dal Negro, A.: Crystal-chemical characterization of blue amphiboles. Proc. XI International Mineralogical Congress, Novosibirsk, Sept. 4–10, 1978 (in press)
Yang, C.N.: The spontaneous magnetization of a two-dimensional Ising model. Phys. Rev. 85, 808–816 (1952)
Zory, P.: Nuclear electrical-field gradient determination utilizing the Mössbauer effect (Fe57). Phys. Rev. 140, 1401–1407 (1965)
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Work performed under the auspices of the U.S. Energy Research & Development Administration under contract No. W-7405-Eng-48
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Borg, R.J., Borg, I.Y. Mössbauer study of behavior of oriented single crystals of riebeckite at low temperatures and their magnetic properties. Phys. Chem. Minerals 5, 219–234 (1980). https://doi.org/10.1007/BF00348571
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DOI: https://doi.org/10.1007/BF00348571