Electronic and magnetic structure of pyroxenes I. Hedenbergite

  • Michael Grodzicki
  • G. Redhammer
  • M. Reissner
  • W. Steiner
  • G. Amthauer
Original Paper
First Online:
Received:
Accepted:

Abstract

The electronic and magnetic structure of the chain silicate hedenbergite (CaFe2+Si2O6) has been investigated by a number of experimental methods (neutron diffraction, Mössbauer spectroscopy, low temperature magnetic measurements), as well as by electronic structure calculations for clusters of different size in the local spin density approximation. The calculated size-converged spectroscopic data (d-d excitation energies, hyperfine parameters) are in quantitative agreement with the respective experimental values. The calculated magnetic coupling constants are about +25 cm−1 and −4 cm−1 for intra-chain and inter-chain coupling, respectively. The latter value shows that weak superexchange via edges of silicon tetrahedra is well reproduced by the calculations, and it is in qualitative agreement with an observed metamagnetic transition at 4.2 K in an external magnetic field with an onset around 4 T but saturation is not achieved in fields up to 14.5 T. The large ferromagnetic intra-chain coupling is attributed to a nearly degenerate ground state. The ratio between the two magnetic coupling constants agrees with earlier estimates on similar compounds. Finally, it is demonstrated how the detailed discussion of the various exchange pathways contributes to an improved understanding of the connection between magnetic properties and the geometrical structure.

Keywords

Clinopyroxenes Electronic structure calculations Mössbauer spectroscopy Superexchange 
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Notes

Acknowledgments

Financial support by the FWF (grant number P18805-N17) is gratefully acknowledged. All calculations have been carried out at the Department of Computer Sciences in Salzburg.

References

  1. Amthauer G, Rossman GR (1984) Mixed valence of iron in minerals with cation clusters. Phys Chem Miner 11:37–51CrossRefGoogle Scholar
  2. Anderson PW (1963) Theory of magnetic exchange interactions: exchange in insulators and semiconductors. Sol State Phys 14:99–214CrossRefGoogle Scholar
  3. Ausserlechner U, Kasperkovits P, Steiner W (1994) Pick-up systems for vibrating sample magnetometers—a theoretical discussion based on magnetic multipole expansions. Meas Sci Technol 5:213–225CrossRefGoogle Scholar
  4. Ausserlechner U, Steiner W, Kasperkovits P (1996) Calibration of vibrating sample magnetometers independent of reference samples. Meas Sci Technol 7:1574–1578CrossRefGoogle Scholar
  5. Bancroft GM, Williams PGL, Burns RG (1971) Mössbauer spectra of minerals along the diopside-hedenbergite tie line. Am Mineral 56:1617–1625Google Scholar
  6. Baum E, Treutmann W, Lottermoser W, Amthauer G (1997) Magnetic properties of the clinopyroxenes aegirine and hedenbergite: a magnetic susceptibility study on single crystals. Phys Chem Miner 24:294–300CrossRefGoogle Scholar
  7. Burns RG (1993) Mineralogical applications of crystal field theory, 2nd edn. Cambridge, UKGoogle Scholar
  8. Cameron M, Sueno S, Prewitt CT, Papike JJ (1973) High-temperature crystal chemistry of acmite, diopside, hedenbergite, jadeite, spodumene, and ureyite. Am Mineral 58:594–618Google Scholar
  9. Coey JMD, Ghose S (1985) Magnetic order in hedenbergite: CaFeSi2O6. Sol State Commun 53:143–145CrossRefGoogle Scholar
  10. Dollase WA, Gustafson WI (1982) 57Fe Mössbauer spectral analysis of the sodic clinopyroxenes. Am Mineral 67:311–327Google Scholar
  11. Dufek P, Blaha P, Schwarz K (1995) Determination of the nuclear quadrupole moment of 57Fe. Phys Rev Lett 75:3545–3548CrossRefGoogle Scholar
  12. Eeckhout SG, De Grave E (2003a) 57Fe Mössbauer-effect studies of Ca-rich, Fe-bearing clinopyroxenes. Part I. Paramagnetic spectra of magnesian hedenbergite. Am Mineral 88:1129–1137Google Scholar
  13. Eeckhout SG, De Grave E (2003b) 57Fe Mössbauer-effect studies of Ca-rich, Fe-bearing clinopyroxenes. Part II. Magnetic spectra of magnesian hedenbergite. Am Mineral 88:1138–1144Google Scholar
  14. Grodzicki M (1980) A self-consistent-charge Xα method I. Theory. J Phys B13:2683–2691Google Scholar
  15. Grodzicki M (1985) Theorie und Anwendungen der Self-Consistent-Charge-Xα Methode; Thesis of habilitation, HamburgGoogle Scholar
  16. Grodzicki M, Männing V, Trautwein AX, Friedt JM (1987) Calibration of isomer shifts and quadrupole coupling constants for 119Sn, 127I and 129I as derived from SCC-Xα calculations and Mössbauer measurements. J Phys B20:5595–5625CrossRefGoogle Scholar
  17. Grodzicki M, Amthauer G (2000) Electronic and magnetic structure of vivianite: cluster molecular orbital calculations. Phys Chem Miner 27:694–702CrossRefGoogle Scholar
  18. Grodzicki M, Heuss-Assbichler S, Amthauer G (2001) Mössbauer investigations and molecular orbital calculations on epidote. Phys Chem Miner 28:675–681CrossRefGoogle Scholar
  19. Grodzicki M, Redhammer G, Amthauer G, Schünemann V, Trautwein A, Velickov B, Schmid-Beurmann P (2003) Electronic structure of Fe-bearing lazulites. Am Mineral 88:481–488Google Scholar
  20. Grodzicki M, Topa D, Bieniok A, Redhammer G, Lottermoser GJ, Paar W, Amthauer G (2004) Electronic and magnetic structure of ludlamite: spectroscopic and theoretical investigations. 32nd International Geological Congress, Abstracts, part I: 549, FlorenceGoogle Scholar
  21. Illas F, de Moreira IPR, de Graaf C, Castell O, Casanovas J (1997) Absence of collective effects in Heisenberg systems with localized magnetic moments. Phys Rev B56:5069–5072Google Scholar
  22. Johnson CE (1967) Hyperfine interactions in ferrous fluosilicates. Proc Phys Soc 92:748–757CrossRefGoogle Scholar
  23. Keutel H, Käpplinger I, Jäger EG, Grodzicki M, Schünemann V, Trautwein AX (1999) Structural, magnetic and electronic properties of a pentacoordinated intermediate-spin (S=3/2) iron(III) complex with a macrocyclic [N 4]2− ligand. Inorg Chem 38:2320–2327CrossRefGoogle Scholar
  24. Lauer S, Marathe VR, Trautwein AX (1979) Sternheimer shielding using various approximations. Phys Rev A19:1852–1861Google Scholar
  25. Lebernegg S, Amthauer G, Grodzicki M (2008) Single-centre MO theory of transition metal complexes. J Phys B41 035102:1–7Google Scholar
  26. Mørup S, Both E (1975) Nucl. Instrum Methods 124:435Google Scholar
  27. Noodleman L (1981) Valence bond description of antiferromagnetic coupling in transition metal dimers. J Chem Phys 74:5737–5743CrossRefGoogle Scholar
  28. Ray SN, Das TP (1977) Nuclear quadrupole interaction in the Fe2+ ion including many-body effects. Phys Rev B16:4794–4804Google Scholar
  29. Redhammer GJ (1996) Untersuchungen zur Kristallchemie und Kristallphysik von synthetischen C2/c Klinopyroxenen im System Hedenbergit CaFe2+Si2O6-Akmit NaFe3+Si2O6. PhD thesis, University of SalzburgGoogle Scholar
  30. Redhammer GJ, Amthauer G, Roth G, Tippelt G, Lottermoser W (2006) Single-crystal X-ray diffraction and temperature dependent 57Fe Mössbauer spectroscopy on the hedenbergite-aegirine (Ca,Na)(Fe2+, Fe3+)Si2O6 solid solution. Am Mineral 91:1271–1292CrossRefGoogle Scholar
  31. Redhammer GJ, Roth G, Treutmann W, Paulus W, André G, Pietzonka C, Amthauer G (2008) Magnetic ordering and spin structure in Ca-bearing clinopyroxenes CaM2+(Si,Ge)2O6, M=Fe, Ni, Co, Mn. J Sol State Chem 181:3163–3176CrossRefGoogle Scholar
  32. Rodriguez-Carvajal J (2001) Recent developments of the program FULLPROF. Commission on Powder Diffraction (IUCr) Newsletter 25:12–19Google Scholar
  33. Slater JC (1974) Quantum theory of molecules and solids, vol 4. McGraw-Hill, New YorkGoogle Scholar
  34. Stanek J, Hafner SS, Regnard JR, El Goresy A (1986) Temperature-dependent hyperfine parameters in CaFeSi2O6. Hyperfine Inter 28:829–832CrossRefGoogle Scholar
  35. Tennant WC, McCammon CA, Miletich R (2000) Electric-field gradient and mean-squared-displacement tensors in hedenbergite from single-crystal Mössbauer milliprobe measurements. Phys Chem Miner 27:156–163CrossRefGoogle Scholar
  36. Varret F (1976) Mössbauer spectra of paramagnetic powders under applied field: Fe2+ in fluosilicates. J Phys Chem Solids 37:265–271CrossRefGoogle Scholar
  37. Wiedenmann A, Regnard JR (1986) Neutron diffraction study of the magnetic ordering in pyroxenes FexMg1-xSiO3. Sol State Commun 57:499–504CrossRefGoogle Scholar
  38. Weber SU, Grodzicki M, Geiger CA, Lottermoser W, Tippelt G, Redhammer GJ, Bernroider M, Amthauer G (2007) 57Fe Mössbauer measurements and electronic structure calculations on natural lawsonite. Phys Chem Miner 34:1–9CrossRefGoogle Scholar

Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  • Michael Grodzicki
    • 1
  • G. Redhammer
    • 1
  • M. Reissner
    • 2
  • W. Steiner
    • 2
  • G. Amthauer
    • 1
  1. 1.Department of Materials Research and PhysicsUniversity of SalzburgSalzburgAustria
  2. 2.Institute of Solid State PhysicsVienna University of TechnologyViennaAustria

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