NMR evidence for selective enhancement of Mo magnetic moment by electron doping inSr2−xLaxFeMoO6

摘要: ${}^{95,97}\mathrm{Mo}$ NMR experiments have been performed on a series of ${\mathrm{Sr}}_{2}{\mathrm{FeMoO}}_{6}$ and electron-doped ${\mathrm{Sr}}_{2\ensuremath{-}x}{\mathrm{La}}_{x}{\mathrm{FeMoO}}_{6}$ ceramics. A detailed analysis the spectra from pristine conclusively shows that Mo hyperfine field is mainly due to atomic magnetic moments. No contribution transferred has observed, confirming absence s electrons in conduction band. Upon La doping, frequency (hyperfine field) gradually increases, proving concentration spin-polarized at ion enhanced by substitution. simple linear correlation between moment sites Curie temperature system found. Implications for understanding electronic structure ferromagnetic coupling these systems are underlined.