Use of the isotope 57Fe for neutron-diffraction determination of positions of iron atoms in the superconductor Y1Ba2(Cu1-xFex)3Oy
Balagurov A. M. , Lyubutin I. S., Mironova G. M., Huan Chan Gen, Shapiro A. Ya.
A neutron-diffraction structural analysis has been made of the system YIBa2(Cu1 _xFex )3)Oy (0.0<x<0.27), in which the iron was enriched to 95.7% in the isotope 57Fe. Up to x0 — 0.10, the iron atoms lie exclusively at Cu 1 sites. At a higher concentration χ = x0 + Ajc, the "excess" iron Δλ; is distributed equiprobably between Cu 1 and Cu2 sites. The introduction of iron results in the capture of additional oxygen, in an amount of 0.5 of an oxygen atom per iron cation.