Effect of H on the crystalline and magnetic structures of the Y-Co3 H(D) system. II YCo-H(D) from X-ray and neutron powder diffraction

Article English OPEN
Liu, J ; Cui, X-Y ; Georgiev, P A ; Morrison, I ; Ross, DK ; Roberts, M ; Anderson, KA ; Telling, M ; Fort, D

The crystalline and magnetic structures of the YCo3\ud -H(D) system have been investigated by means of x-ray\ud and neutron diffraction with the objective of understanding the complex magnetic changes that are observed in\ud this system as hydrogen is added. Synchrotron x-ray diffraction (XRD) patterns were first refined to yield the\ud lattice parameters and coordination of Y and Co atoms in the metal and two B-hydride phases while XRD was\ud used for the y phase. In situ neutron powder diffraction measurements of YCo3Dx were then made in all four\ud phases to determine the deuterium site occupancies and magnetic structures. The site occupancies were also\ud rationalized using the Westlake geometric model. The highest hydrogen concentration measured was\ud YCo3H4.6\ud . Using the Westlake model, we conclude that the saturated hydrogen content would be YCo3H5\ud . Our\ud results reported here and in Part I (Phys. Rev. B 76, 184443 (2007)) have enabled us to rationalize the changes\ud in the magnetic structures in terms of changes in the cobalt-cobalt distance caused by the addition of hydrogen.\ud In particular, in the antiferromagnetic y phase, we observe Co atomic displacements that enable the structure\ud to adopt a particular antiferromagnetic structure in a manner that is reminiscent of a Peierls distortion as\ud observed in transitions from the conducting to nonconducting hydrides on addition of hydrogen in YH3.
  • References (23)
    23 references, page 1 of 3

    1 M. Yamaguchi, H. Ikeda, T. Ohta, T. Katayama, and T. Goto, J. Less-Common Met. 106, 165 1985 .

    2 X. Y. Cui, J. Liu, I. Morrison, and D. K. Ross, J. Alloys Compd. 404-406, 136 2005 .

    3 M. Yamaguchi, D. K. Ross, T. Goto, and T. Ohta, Z. Phys. Chem., Neue Folge 145, 355 1985 .

    4 M. Yamaguchi, I. Yamamoto, Y. Fugita, and T. Goto, Z. Phys. Chem., Neue Folge 163, 677 1989 .

    5 M. I. Bartashevich, H. A. Katori, T. Goto, I. Yamamoto, and M. Yamaguchi, Physica B 201, 135 1994 .

    6 M. J. Benham, S. M. Bennington, D. K. Ross, D. Noreus, and M. Yamaguchi, Z. Phys. Chem., Neue Folge 163, 283 1989 .

    7 V. V. Burnasheva, V. A. Yartys, S. P. Solov'ev, N. V. Fadeeva, and K. N. Semenenko, Sov. Phys. Crystallogr. 274, 409 1982 .

    8 M. I. Bartashevich, A. N. Pirogov, V. I. Voronin, T. Goto, M. Yamaguchi, and I. Yamagoto, J. Alloys Compd. 231, 104 1995 .

    9 J. Liu, D. P. Broom, P. A. L. Georgiev, and D. K. Ross, J. Alloys Compd. 356-357, 174 2003 .

    10 D. G. Westlake, J. Less-Common Met. 75, 177 1980 .

  • Metrics
    No metrics available
Share - Bookmark