Diamagnetic Behavior in Nanoparticle Hematite?
| Autor: | David K. Potter, Petar A. Petrov, Arfan Ali |
|---|---|
| Rok vydání: | 2017 |
| Předmět: |
0301 basic medicine
Materials science Condensed matter physics Nanoparticle Hematite 010502 geochemistry & geophysics Magnetic hysteresis 01 natural sciences Dispersant Magnetic susceptibility 03 medical and health sciences Paramagnetism 030104 developmental biology Nuclear magnetic resonance visual_art visual_art.visual_art_medium Antiferromagnetism Diamagnetism 0105 earth and related environmental sciences |
| Zdroj: | Journal of Modern Physics. :1013-1019 |
| ISSN: | 2153-120X 2153-1196 |
| DOI: | 10.4236/jmp.2017.87063 |
| Popis: | A paper by Mi et al. [1] suggested that certain nano-sized hematite (α-Fe2O3) particles had diamagnetic properties at room temperature. Since diamagnetic behavior is not a property normally attributed to hematite particles (hematite is generally regarded as a canted antiferromagnetic material at room temperature) we decided to test the validity of the suggestions in [1] by performing magnetic susceptibility and magnetic hysteresis measurements on a series of hematite nanoparticles with average sizes of 8 nm, 30 nm and 40 nm in diameter. We initially considered two possible explanations for the apparent diamagnetic behavior of the nanoparticles in [1]: either 1) the hematite nanoparticles themselves exhibited this unusual diamagnetic behavior, or 2) the diamagnetic response was simply the signal created by a diamagnetic dispersant that was overriding a weak positive magnetic susceptibility signal of the hematite nanoparticles. Our experiments strongly suggested the latter explanation that the apparent “diamagnetic” behavior seen in [1] was caused by a diamagnetic dispersant dominating the magnetic properties of the dispersed hematite nanoparticles. |
| Databáze: | OpenAIRE |
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