| Record |
| Author |
Dinger, J.; Friedrich, T.; Reimann, T.; Toepfer, J. |
| Title |
NiMn₂O₄ revisited : temperature-dependent cation distribution from in situ neutron diffraction and thermopower studies |
Type |
A1 Journal article |
Year  |
2023 |
Publication |
Journal of the American Ceramic Society |
Abbreviated Journal |
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| Volume |
106 |
Issue |
3 |
Pages |
1834-1847 |
| Keywords |
A1 Journal article; Electron microscopy for materials research (EMAT) |
| Abstract |
The cation distribution of the negative temperature coefficient (NTC) thermistor spinel NiMn2O4 was studied in the temperature range from 55 to 900 degrees C, using a combined in situ neutron diffraction and thermopower study. Rietveld refinements of in situ neutron diffraction data reveal a temperature dependence of the degree of inversion with an inversion parameter of 0.70(1) at 900 degrees C and 0.87(1) at 55 degrees C. Thermopower measurements were evaluated using a modified Heikes formula, and the [Mn4+]/[Mn3+] ratio on octahedral sites of the spinel structure was calculated considering spin and orbital degeneracy. The inversion degree and disproportionation parameter, determined independently as function of temperature, were used to calculate the cation distribution of NiMn2O4 in the whole temperature range. At high temperature, within the stability range of the spinel, the cation distribution is characterized by a moderate degree of inversion with a concentration of NiB2+${\mathrm{Ni}}\mathrm{B}< |
| Address |
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| Corporate Author |
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Thesis |
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| Publisher |
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Place of Publication |
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Editor |
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| Language |
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Wos |
000880360600001 |
Publication Date |
2022-10-21 |
| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
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Series Issue |
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Edition |
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| ISSN |
0002-7820 |
ISBN |
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Additional Links |
UA library record; WoS full record |
| Impact Factor |
3.9 |
Times cited |
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Open Access |
OpenAccess |
| Notes |
|
Approved |
Most recent IF: 3.9; 2023 IF: 2.841 |
| Call Number |
UA @ admin @ c:irua:192087 |
Serial |
7326 |
| Permanent link to this record |
