Effect of Structural Parameters on Superconductivity in Fluorine-Free LnFeAsO1-y (Ln = La, Nd)

  title={Effect of Structural Parameters on Superconductivity in Fluorine-Free LnFeAsO1-y (Ln = La, Nd)},
  author={Chang Hee Lee and Akira Iyo and Hiroshi Eisaki and Hijiri Kit{\^o} and Mar{\'i}a Teresa Fern{\'a}ndez-D{\'i}az and T. Ito and Kunihiro Kihou and Hirofumi Matsuhata and M. Braden and K. N. Yamada},
  journal={Journal of the Physical Society of Japan},
The crystal structure of LnFeAsO 1- y (Ln = La, Nd) has been studied by the powder neutron diffraction technique. The superconducting phase diagram of NdFeAsO 1- y is established as a function of oxygen content which is determined by Rietveld refinement. The small As–Fe bond length suggests that As and Fe atoms are connected covalently. FeAs 4 -tetrahedrons transform toward a regular shape with increasing oxygen deficiency. Superconducting transition temperatures seem to attain maximum values… Expand

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