On the magnetic anisotropy and susceptibility of Fe(NH 4 SO 4 ) 2 , 6H 2 O

1961 ◽  
Vol 261 (1305) ◽  
pp. 207-214 ◽  
Keyword(s):  
Thermal Expansion ◽  
Magnetic Anisotropy ◽  
Crystal Lattice ◽  
Crystal Field ◽  
Coupling Coefficient ◽  
Orbit Coupling ◽  
Spin Orbit Coupling ◽  
Spin Orbit ◽  
Anisotropic Part ◽  
Free Ion

The theory of magnetic anisotropy and susceptibility of Fe 2+ in Tutton salts has been worked out on the basis of Abragam & Pryce’s method. It is found that the anisotropic part of the crystal field changes with temperature owing to the thermal expansion of the crystal lattice. The spin-orbit coupling coefficient has to be decreased by ~ 20 % from its free ion value of - 103 cm -1 which indicates some amount of overlap between the 3 d -Fe 2+ and 8 - and p -O 2- charge clouds. The agreement of the theoretical values with the experiment is good within the limitations of the approximations involved.

Anomalous thermal expansion in orthorhombic perovskiteSrIrO3: Interplay between spin-orbit coupling and the crystal lattice

2014 ◽  
Vol 89 (21) ◽  
Author(s):  
Peter E. R. Blanchard ◽  
Emily Reynolds ◽  
Brendan J. Kennedy ◽  
Justin A. Kimpton ◽  
Maxim Avdeev ◽  
...  
Keyword(s):  
Thermal Expansion ◽  
Crystal Lattice ◽  
Orbit Coupling ◽  
Spin Orbit Coupling ◽  
Spin Orbit ◽  
Anomalous Thermal Expansion

Ground configuration splitting in UCl5

1977 ◽  
Vol 55 (10) ◽  
pp. 937-942 ◽  
Author(s):  
A. F. Leung ◽  
Ying-Ming Poon
Keyword(s):  
Crystal Field ◽  
Energy Levels ◽  
Orbit Coupling ◽  
Spin Orbit Coupling ◽  
Spin Orbit ◽  
Coupling Constant ◽  
Point Charge Model ◽  
X Ray Crystallography ◽  
Charge Model ◽  
Crystal Field Parameters

The absorption spectra of UCl5 single crystal were observed in the region between 0.6 and 2.4 μm at room, 77, and 4.2 K temperatures. Five pure electronic transitions were assigned at 11 665, 9772, 8950, 6643, and 4300 cm−1. The energy levels associated with these transitions were identified as the splittings of the 5f1 ground configuration under the influence of the spin–orbit coupling and a crystal field of C2v symmetry. The number of crystal field parameters was reduced by assuming the point-charge model where the positions of the ions were determined by X-ray crystallography. Then, the crystal field parameters and the spin–orbit coupling constant were calculated to be [Formula: see text],[Formula: see text], [Formula: see text], and ξ = 1760 cm−1. The vibronic analysis showed that the 90, 200, and 320 cm−1 modes were similar to the T2u(v6), T1u(v4), and T1u(v3) of an UCl6− octahedron, respectively.

scholarly journals Spin-orbit coupling induced magnetic anisotropy and large spin wave gap in NaOsO3

2018 ◽  
Vol 2 (11) ◽  
pp. 115016 ◽  
Author(s):  
Avinash Singh ◽  
Shubhajyoti Mohapatra ◽  
Churna Bhandari ◽  
Sashi Satpathy
Keyword(s):  
Magnetic Anisotropy ◽  
Spin Wave ◽  
Orbit Coupling ◽  
Spin Orbit Coupling ◽  
Spin Orbit ◽  
Induced Magnetic Anisotropy ◽  
Spin Wave Gap ◽  
Large Spin

Determination of the spin orbit coupling and crystal field splitting in wurtzite InP by polarization resolved photoluminescence

2018 ◽  
Vol 112 (7) ◽  
pp. 071903 ◽  
Author(s):  
Nicolas Chauvin ◽  
Amaury Mavel ◽  
Ali Jaffal ◽  
Gilles Patriarche ◽  
Michel Gendry
Keyword(s):  
Crystal Field ◽  
Orbit Coupling ◽  
Crystal Field Splitting ◽  
Spin Orbit Coupling ◽  
Spin Orbit ◽  
Field Splitting

Space-group operations and time-reversal for a Dirac electron in a crystal field

1958 ◽  
Vol 243 (1235) ◽  
pp. 546-554 ◽  
Keyword(s):  
Dirac Equation ◽  
Crystal Field ◽  
Time Reversal ◽  
Orbit Coupling ◽  
Spin Orbit Coupling ◽  
Spin Orbit ◽  
Band Theory ◽  
Space Group ◽  
Basic Formalism ◽  
Dirac Electron

It is shown in the first part how the basic formalism of the theory of spin-orbit coupling in the band theory of crystals can be deduced at once from the Dirac equation without the usual ambiguities over improper rotations associated with the formalism based on the Pauli-Schrödinger equation. In the second part it is shown that the original proofs of the time-reversal theorems given by Wigner are unnecessarily complicated.

Crystalline electric fields in hydrated Co 2+ salts

1961 ◽  
Vol 261 (1304) ◽  
pp. 43-52 ◽  
Keyword(s):  
Magnetic Susceptibility ◽  
Electric Fields ◽  
Coupling Coefficient ◽  
Experimental Results ◽  
Spin Orbit Coupling ◽  
Spin Orbit ◽  
Anisotropic Field ◽  
Free Ion ◽  
Crystalline Electric Fields ◽  
Field Separation

The theoretical expressions for the magnetic susceptibility and anisotropy of Co 2+ ion in hexahydrated salts have been derived on the basis of Abragam & Pryce’s theory and compared with the experimental results for three Tutton salts. Agreement with experiment is very good provided it is assumed that for each salt the value of the asymmetric field separation A varies with temperature. It appears that the magnitude of A depends more upon the alkali radicals than upon the acid radicals. The value of the spin-orbit coupling coefficient ζ in Co 2+ salts is practically the same as the free ion value, indicating very little overlap between the 3 d -Co 2+ and s . and p-O 2- charge clouds. The cubic and anisotropic field parameters G, H and I are different for divalent Co 2+ and trivalent V 3+ , as is to be expected.

scholarly journals Low-field Magnetic Anisotropy of Sr2IrO4

2022 ◽  
Author(s):  
Muhammad Nauman ◽  
Tayyaba Hussain ◽  
Joonyoung Choi ◽  
Nara Lee ◽  
Young Jai Choi ◽  
...  
Keyword(s):  
Magnetic Anisotropy ◽  
Exchange Interaction ◽  
Exchange Interactions ◽  
Orbit Coupling ◽  
Spin Orbit Coupling ◽  
Spin Orbit ◽  
Easy Magnetization ◽  
Magnetic Exchange ◽  
Crystal Field Effect ◽  
Out Of Plane

Abstract Magnetic anisotropy in strontium iridate (Sr2IrO4) is essential because of its strong spin–orbit coupling and crystal field effect. In this paper, we present a detailed mapping of the out-of-plane (OOP) magnetic anisotropy in Sr2IrO4 for different sample orientations using torque magnetometry measurements in the low-magnetic-field region before the isospins are completely ordered. Dominant in-plane anisotropy was identified at low fields, confirming the b axis as an easy magnetization axis. Based on the fitting analysis of the strong uniaxial magnetic anisotropy, we observed that the main anisotropic effect arises from a spin–orbit-coupled magnetic exchange interaction affecting the OOP interaction. The effect of interlayer exchange interaction results in additional anisotropic terms owing to the tilting of the isospins. The results are relevant for understanding OOP magnetic anisotropy and provide a new way to analyze the effects of spin–orbit-coupling and interlayer magnetic exchange interactions. This study provides insight into the understanding of bulk magnetic, magnetotransport, and spintronic behavior on Sr2IrO4 for future studies.

Photoelectron spectra and electronic structure of diatomic alkali halides

1974 ◽  
Vol 341 (1625) ◽  
pp. 147-161 ◽  
Keyword(s):  
Coupling Coefficient ◽  
Alkali Halides ◽  
Orbit Coupling ◽  
Photoelectron Spectra ◽  
Ionic Character ◽  
Spin Orbit Coupling ◽  
Spin Orbit ◽  
Ionic Model ◽  
Halogen Atoms ◽  
A Value

The He I photoelectron spectra of the chlorides, bromides and iodides of Na, K, Rb and Cs have been recorded in the vapour state by a molecular beam technique. The spectra exhibit features which have been interpreted on the basis of a completely ionic model in keeping with the treatments usually applied to ionic solids. To explain structure in the spectra of the lighter molecules it has been necessary to discuss polarization of the halogen atoms by the alkali metal ions. For the heavier molecules such as KI, RbI and Csl the spectra of the monomers consist of two fairly broad bands corresponding to ionization of the X­­­­ˉmoiety to its 2 P 3/2 and 2 P ½ states. These have a 2/1 intensity ratio and a separation equal to 3/2 times the appropriate spin-orbit coupling coefficient. In the case of NaI the 2 P 3/2 state is split by the strong electrostatic field of the Na + ion into states possessing 2 ∏ 3/2 and 2 ∏ ½ character. This is accompanied by a shift of the 2 P ½ state to higher energies as it gradually assumes 2 ∑ character. The result is an increase of the mean 2 P 3/2 – 2 P ½ separation to a value greater than that to be expected from spin-orbit coupling alone. This increase becomes more pronounced for the bromides and chlorides where the spin-orbit coupling coefficient is smaller. For NaCl the separation of the 2 P 3/2 and 2 P ½ bands shows clearly that the 2 P½ band possesses considerable 2 ∑ character. In terms of partial ionic character, increased polarization of the halogen atom is related to increased covalent character of the MX bond. The lighter molecules can therefore be said to be the least ionic in this description. The proportion of dimers to monomers observed in the spectra is found to fall as the molecules become more ionic, i. e. as the halogen atoms become less polarized.

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