The Physics of Metals and Metallography

, Volume 106, Issue 5, pp 481–489 | Cite as

Magnetic properties of the Mn1.9 − x Co x Ge compounds with a hexagonal crystal structure

  • P. E. Markin
  • N. V. Mushnikov
  • V. I. Khrabrov
  • M. A. Korotin
Electrical and Magnetic Properties


Concentrational dependences of the lattice parameters, spontaneous magnetic moment, and magnetic ordering temperature of nonstoichiometric Mn1.9 − x Co x Ge (0.8 < x < 1.65) compounds with a hexagonal crystal structure of the Ni2In type have been studied. As the Co content (x) increases from 1.1 to 1.2, the Curie temperature and magnetic moment were found to increase abruptly. The magnetization curves measured for oriented single crystals indicate the presence of a concentrational spin-reorientation transition in this system. The experimental data obtained are discussed taking into account the results of energy-band electronic-structure calculations.

PACS numbers

75.50.Cc 75.30.Kz 


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  1. 1.
    K. Ullakko, J. K. Huang, C. Kantner, et al., “Large Magnetic-Field-Induced Strains in Ni2MnGa Single Crystals,” Appl. Phys. Lett. 69, 1966–1968 (1996).CrossRefADSGoogle Scholar
  2. 2.
    R. Kainuma, Y. Imano, W. Ito, et al., “Magnetic-Field-Induced Shape Recovery by Reverse Phase Transformation,” Nature 439, 957–960 (2006).PubMedCrossRefADSGoogle Scholar
  3. 3.
    T. Kakeshita, T. Takeuchi, T. Fukuda, et al., “Magnetic Field-Induced Martensitic Transformation and Giant Magnetostriction in Fe-Ni-Co-Ti and Ordered Fe3Pt Shape Memory Alloys,” Mater. Trans. 41, 882–886 (2000).Google Scholar
  4. 4.
    K. Koyama, M. Sakai, S. Takeshi, et al., “Field-Induced Martensitic Transformation in New Ferromagnetic Shape Memory Compound Mn1.07Co0.92Ge,” Jpn. J. Appl. Phys. 43, 8036–8039 (2004).CrossRefADSGoogle Scholar
  5. 5.
    V. Johnson, “Diffusionless Orthorhombic to Hexagonal Transitions in Ternary Silicides and Germanides,” Inorg. Chem. 14, 1117–1120 (1975).CrossRefGoogle Scholar
  6. 6.
    S. Nizol, A. Bombik, W. Bazela, et al., “Crystal and Magnetic Structure of CoxNi1 − xMnGe System,” J. Magn. Magn. Mater. 27, 281–292 (1982).CrossRefADSGoogle Scholar
  7. 7.
    T. Kanomata, H. Ishigaki, T. Suzuki, et al., “Magneto-Volume Effect of MnCo1 − xGe (0 ≤ x ≤ 0.2),” J. Magn. Magn. Mater. 140–144, 131–132 (1995).CrossRefGoogle Scholar
  8. 8.
    J. T. Wang, D. S. Wang, C. Chen, et al., “Vacancy Induced Structural and Magnetic Transition in MnCo1 − xGe,” Appl. Phys. Lett. 89, 262504–1 (2006).CrossRefADSGoogle Scholar
  9. 9.
    S. Kaprzyk and S. Nizol, “The Electronic Structure of CoMnGe with the Hexagonal and Orthorhombic Crystal Structure,” J. Magn. Magn. Mater. 87, 267–275 (1990).CrossRefADSGoogle Scholar
  10. 10.
    W. Jeitschko, “A High-Temperature X-ray Study of the Displacive Phase Transition in MnCoGe,” Acta Crystallogr., Sect B: Struct. Sci. 31, 1187–1190 (1975).CrossRefGoogle Scholar
  11. 11.
    E. F. Wasserman, “Invar: Moment-Volume Instabilities in Transition Metals and Alloys,” in Ferromagnetic Materials, Ed. by K. H. J. Buschow and E. P. Wohlfarth (North-Holland, Amsterdam, 1990), Vol. 5, pp. 237–321.CrossRefGoogle Scholar
  12. 12.
    G.F. Zhou and H. Bakker, “Spin-Glass Behavior of Amorphous Co2Ge Synthesized by Mechanical Milling,” Phys. Rev. Letters 72(14), 2290–2293 (1994).CrossRefADSGoogle Scholar
  13. 13.
    V. Yu. Irkhin and Yu. P. Irkhin, Electron Structure, Physical Properties and Correlation Effects in d and f Metals and Their Compounds (Ural. Otd. Ross. Akad. Nauk, Ekaterinburg, 2004).Google Scholar
  14. 14.
    A. Szytula, W. Bazela, and S. Radenkovic, “Crystal and Magnetic Structure of the CoMn1 − xTixGe System,” J. Magn. Magn. Mater. 38, 99–104 (1983).CrossRefADSGoogle Scholar

Copyright information

© Pleiades Publishing, Ltd. 2008

Authors and Affiliations

  • P. E. Markin
    • 1
    • 2
  • N. V. Mushnikov
    • 1
  • V. I. Khrabrov
    • 1
  • M. A. Korotin
    • 1
  1. 1.Institute of Metal Physics, Ural DivisionRussian Academy of SciencesEkaterinburgRussia
  2. 2.Ural State UniversityEkaterinburgRussia

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