ISSN:
1573-4803
Source:
Springer Online Journal Archives 1860-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Abstract Electron spin resonance linewidths of Fe3+ in single crystal MgO at 9 GHz were examined experimentally and theoretically for a range of Fe3+ concentration. In contrast to the behaviour expected from dipolar broadening the experimental derivative peak-to-peak linewidth for the 1/2 ↔ −1/2 transition, about 0.6 mT at 77 K and a polar angle of 0°, was independent of concentration from 140 to 8500 ppm. The calculated dipolar linewidths greatly exceeded those observed and values of the ratio of moments M 4 1/4 /M 2 1/2 derived from the experimental data lay between 1.33 and 1.48. Optical examination, coupled with heat-treatment experiments, confirmed that the predominant valency state present was Fe3+. The data suggested that Fe3+ entered the lattice substitutionally, occupying magnesium sites, and that the linewidths were determined by exchange narrowing over the whole concentration range examined.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1007/BF00541079
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