Abstract
Elastic- and electrostatic-energy considerations are insufficient for an explanation of cation ordering between tetrahedral and octahedral sites in spinels. Tetrahedral, octahedral, and square covalent bonds are also important when cations are to be accommodated in these sites. The square bonds in octahedral sites can cause the tetragonal distortion observed in ${\mathrm{Mn}}_{3}$${\mathrm{O}}_{4}$ $\ensuremath{\gamma}$-${\mathrm{Mn}}_{2}$${\mathrm{O}}_{3}$, Zn${\mathrm{Mn}}_{2}$${\mathrm{O}}_{4}$, Cu${\mathrm{Fe}}_{2}$${\mathrm{O}}_{4}$, Cu${\mathrm{Cr}}_{2}$${\mathrm{O}}_{4}$, Ca${\mathrm{In}}_{2}$${\mathrm{O}}_{4}$, Cd${\mathrm{In}}_{2}$${\mathrm{O}}_{4}$, and metallic indium. A new magnetic exchange mechanism, "semicovalent exchange," which is consistent with the covalent model, is used to explain the magnetic properties of spinels.
Keywords
Affiliated Institutions
Related Publications
<i>Ab initio</i>lattice dynamics and phase transformations of<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:mi mathvariant="normal">Zr</mml:mi><mml:msub><mml:mi mathvariant="normal">O</mml:mi><mml:mn>2</mml:mn></mml:msub></mml:mrow></mml:math>
Zirconia, $\mathrm{Zr}{\mathrm{O}}_{2}$, is one of the most important ceramic materials in modern technology. Its versatility is closely related to phase transformations. Althou...
Energy of Lattice Distortion in Cold Worked Permalloy
The lattice distortion produced by severe cold working of permalloy of 70 percent Ni content has been studied by measuring the broadenin of the reflection of the Fe $K\ensuremat...
Domain Structure of Rochelle Salt and K<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">H</mml:mi></mml:mrow><mml:mrow><mml:mn>2</mml:mn></mml:mrow></mml:msub></mml:mrow></mml:math>P<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mrow><mml:msub><mml:mrow><mml:mi mathvariant="normal">O</mml:mi></mml:mrow><mml:mrow><mml:mn>4</mml:mn></mml:mrow></mml:msub></mml:mrow></mml:math>
It has been verified by means of the polarization microscope that rochelle salt in the ferroelectric state consists of many domains. The domain structure in an annealed crystal ...
Magnetic, transport, and optical properties of monolayer copper oxides
The authors review the results of a wide variety of experiments on materials such as ${\mathrm{La}}_{2}{\mathrm{CuO}}_{4}$ and ${\mathrm{Nd}}_{2}{\mathrm{CuO}}_{4}$ that contain...
From ultrasoft pseudopotentials to the projector augmented-wave method
The formal relationship between ultrasoft (US) Vanderbilt-type pseudopotentials and Bl\"ochl's projector augmented wave (PAW) method is derived. It is shown that the total energ...
Publication Info
- Year
- 1955
- Type
- article
- Volume
- 98
- Issue
- 2
- Pages
- 391-408
- Citations
- 694
- Access
- Closed
External Links
Social Impact
Social media, news, blog, policy document mentions
Citation Metrics
Cite This
Identifiers
- DOI
- 10.1103/physrev.98.391