Abstract
The Mo-95 and Mo-97 NMR spin-echo study of (Sr,Ba,La)(2)Fe1+yMo1-yO6 double perovskites is reported. Powder samples of Ba1.44Sr0.36La0.2FeMoO6 and (Ba0.8Sr0.2)(2-2x)La(x)not equal(x)Fe(1+y)Mo(1-y)O(6), where not equal denotes vacancies, for: x = 0, y = 0; x = 0.1, x = 0.2 and x = 0.3, y = 0 and y = 0.2 were measured at 4.2 K and no applied magnetic field. NMR signals are observed at 55-100 MHz for the main line and 30-55 MHz for low-frequency satellite. The main line and the satellite are attributed to the ideal and defect positions of Mo atoms. La and vacancy doping introduce more defects, however, increasing the Fe/Mo ratio decreases the amount of defect Mo sites. La doping causes a satellite pattern at the high frequency side of the spectrum, which is related to different numbers of the La next neighbours. The effect is attributed to an increase in the electron density and the corresponding magnetic moment at the adjacent Mo sites and reveals a local character of the electron doping.
Original language | English |
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Pages (from-to) | 759-765 |
Number of pages | 7 |
Journal | Acta Physica Polonica A |
Volume | 106 |
Publication status | Published - Nov 2004 |
Keywords
- SR2FEMOO6