Magnetization and Mossbauer studies of 57Fe doped SrCoO3

Fe-57 (1%) doped SrCoO3 obtained by high-pressure method, has been investigated by magnetization and Mossbauer spectroscopy studies (MS) in the temperature range 4.2 K to 300 K. The ferromagnetic ordering temperature T-C obtained is 272(2) K. Isothermal magnetization curves have been measured at various temperatures, from which the saturation moments (M-sat) have been deduced. The Fe-57 MS spectra display standard six-line patterns with an isomer shift typical of Fe3+ and a very small quadrupole splitting (QS = 0.14(1) mm/s above T-C). The magnetic hyperfine field at 4.2 K is 276(1) kOe. The temperature dependencies of the iron hyperfine field and M-sat (1.83 mu(B) at 5 K) are almost identical. This shows that the Fe3+ is replacing Co4+, both of the same electronic configuration. They also interact similarly, namely the Fe-Co exchange is almost identical to the Co-Co exchange.