The rare-earth site of samples having the compositions (Fe,Cu)Sr2(Eu,Ce)nCu2O4+2 n+z (n=2 and 3) were studied by151Eu Mössbauer spectroscopy. The results obtained are compared with measurements of EuBa2Cu3O7-δ (1:2:3) and Bi2Sr2(Ca1-yEuy)Cu2O8+E (2:2:1:2) samples. The full quadrupole Hamiltonian of the 21.5-keV γ-transition was applied in analyzing the measured spectra. Simultaneous fitting of spectra recorded from crystallites oriented in various directions was used to determine the hyperfine parameters of the n= 2 and 3 samples. Two different electric field gradients, not discernible in simple random crystallite measurements, were obtained for the n=3 series. © 1994 J.C. Baltzer AG, Science Publishers.
- High-Tc superconductors
- Mössbauer spectroscopy