Journal ArticleDOI
Anisotropic Superexchange Interaction and Weak Ferromagnetism
TLDR
In this paper, the Anderson theory of superexchange was extended to include spin-orbit coupling and the antisymmetric spin coupling suggested by Dzialoshinski from purely symmetry grounds and the symmetric pseudodipolar interaction were derived.Abstract:
A theory of anisotropic superexchange interaction is developed by extending the Anderson theory of superexchange to include spin-orbit coupling. The antisymmetric spin coupling suggested by Dzialoshinski from purely symmetry grounds and the symmetric pseudodipolar interaction are derived. Their orders of magnitudes are estimated to be ($\frac{\ensuremath{\Delta}g}{g}$) and ${(\frac{\ensuremath{\Delta}g}{g})}^{2}$ times the isotropic superexchange energy, respectively. Higher order spin couplings are also discussed. As an example of antisymmetric spin coupling the case of Cu${\mathrm{Cl}}_{2}$\ifmmode\cdot\else\textperiodcentered\fi{}2${\mathrm{H}}_{2}$O is illustrated. In Cu${\mathrm{Cl}}_{2}$\ifmmode\cdot\else\textperiodcentered\fi{}2${\mathrm{H}}_{2}$O, a spin arrangement which is different from one accepted so far is proposed. This antisymmetric interaction is shown to be responsible for weak ferromagnetism in $\ensuremath{\alpha}$-${\mathrm{Fe}}_{2}$${\mathrm{O}}_{3}$, MnC${\mathrm{O}}_{3}$, and Cr${\mathrm{F}}_{3}$. The paramagnetic susceptibility perpendicular to the trigonal axis is expected to increase very sharply near the N\'eel temperature as the temperature is lowered, as was actually observed in Cr${\mathrm{F}}_{3}$.read more
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Journal ArticleDOI
Tilt engineering of spontaneous polarization and magnetization above 300 K in a bulk layered perovskite
Michael J. Pitcher,Pranab K. Mandal,Matthew S. Dyer,Jonathan Alaria,Pavel Borisov,Hongjun Niu,John B. Claridge,Matthew J. Rosseinsky +7 more
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S. A. Montoya,S. Couture,Jordan Chess,James Lee,James Lee,Noah Kent,Dean Henze,Shantanu Sinha,Mi-Young Im,Mi-Young Im,Stephen D. Kevan,Stephen D. Kevan,Peter Fischer,Peter Fischer,Benjamin J. McMorran,Vitaliy Lomakin,Sujoy Roy,Eric E. Fullerton +17 more
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A symbol approach for classification of molecule-based magnetic materials exemplified by coordination polymers of metal carboxylates
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Mössbauer Effect in α-Fe2O3
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Journal ArticleDOI
Effect of Eu substitution on the crystal structure and multiferroic properties of BiFeO3
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