Chinese Acad Sci, Inst High Energy Phys, Beijing 100080, Peoples R China
; Beijing Univ Aeronaut & Astronaut, Sch Sci, Beijing 100083, Peoples R China
; Beijing Univ Sci & Technol, Dept Met Phys, Beijing 100083, Peoples R China
The ceramic samples with nominal composition of La2/3Ca1/3Mn1-xFexO3 (0.01 less than or equal to x less than or equal to 0.20) were prepared by solid state reaction method. The effect of Fe doping on the Mn site was measured by the positron annihilation technique and Mossbauer spectroscopy. Upon doping, no appreciable structure change and electronic structure change in Mn-O plane were observed in the series of compounds. The Mossbauer parameters show that the iron probe has stable 3+ valance with the high spin state in all samples. Moreover, by examining the shape of the spectra, the tendence can be found that the isomer shift and quadruploe splitting increase with the increasing Fe+3 content. This phenomenon shows the local lattice distortion and the localization of d-electrons with the increasing Fe-doping content.