Abstract
The structure and magnetic properties of sol-gel-synthesized, nanocrystalline KδMnO2 were investigated. The nanoparticles were determined by x-ray diffraction and high-resolution transmission electron microscopy to be single-crystal rods of the cryptomelane phase of MnO2, with a typical particle size of 6 nm × 20 nm. The field and temperature dependence of the magnetization indicates superparamagnetic behavior, with a blocking temperature of 15K. The dependence of the magnetic properties on particle size, surface layers and mixed valency is discussed.
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Stroud, R.M., Carpenter, E., Browning, V.M. et al. Structure and Magnetism of Nanocrystalline KδMnO2. MRS Online Proceedings Library 602, 283–288 (1999). https://doi.org/10.1557/PROC-602-283
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DOI: https://doi.org/10.1557/PROC-602-283