MAGNETIC ORDERING PROPERTIES OF RARE-EARTH IONS IN STRONG CUBIC CRYSTAL FIELDS

Journal Article · Thu Aug 01 04:00:00 EDT 1963 · Physical Review (U.S.) Superseded in part by Phys. Rev. A, Phys. Rev. B: Solid State, Phys. Rev. C, and Phys. Rev. D

DOI:https://doi.org/10.1103/PhysRev.131.932· OSTI ID:4672082

Trammell, G T

A theoretical discussion of some of the effects resulting from the interplay between strong crystalline field torques and weaker exchange torques acting on rare-earth ions is given. The crystalline field is supposed to have cubic symmetry. A semiclassical discussion of the effect of the crystalline field in determining easy directions, anisotropy, and the depression of ground- state ordered moment values for the rare-earth series is given and used to interpret the results of the exact calcuiations. It is shown that for some of the rare earths the crystalline field may be so large that no long-range magnetic order is possible at low temperatures. The theory is applied to the case of the rare-earth phosphides. Adjusting the exchange and crystalline field parameters to yield the observed ordered moment values (and moment directions) of TbP and ErP, one predicts the HoP moment in agreement with the experimental vaiue, and predicts that TmP will not order at all. The holmium flopside'' moment pattern is explained as being due to magnetic dipole forces. The ratio of the sixth- order component of the crystalline potentral to the fourth-order component must be increased some five times over the naively computed value in order to reach agreement with experiment; however, an experimental indication of a possibly important noncubic component of the crystalline potential may change this value appreciably. (auth)

• Research Organization: Rice Univ., Houston, Tex.
• NSA Number: NSA-17-031175
• OSTI ID: 4672082
• Report Number(s): TID-18811; 0031-899X
• Journal Information: Physical Review (U.S.) Superseded in part by Phys. Rev. A, Phys. Rev. B: Solid State, Phys. Rev. C, and Phys. Rev. D, Journal Name: Physical Review (U.S.) Superseded in part by Phys. Rev. A, Phys. Rev. B: Solid State, Phys. Rev. C, and Phys. Rev. D Vol. Vol: 131; ISSN PHRVA
• Country of Publication: Country unknown/Code not available
• Language: English

Related Subjects

ANISOTROPY
CRYSTALS
DIPOLES
ELECTRIC FIELDS
ELECTRIC POTENTIAL
ENERGY LEVELS
EQUATIONS
ERBIUM COMPOUNDS
HOLMIUM COMPOUNDS
INTERACTIONS
IONS
LOW TEMPERATURE
MAGNETIC MOMENTS
MAGNETISM
NUMERICALS
PHOSPHORUS COMPOUNDS
PHYSICS
RARE EARTHS
TERBIUM COMPOUNDS