Magnetic exchange in 2,2'-bipyridyliron(III) chloride

The magnetic susceptibility and anisotropy of cis-bis(2,2'-bipyridyl)dichloroiron(III) tetrachloroferrate(III), cis-[Fe(bpy)2Cl2]+ [FeCl4]-, have been measured between 1.8 and 300 K at magnetic fields up to 1 T. The magnetization on the cation and anion sites has been estimated by means of polarized neutron diffraction measurements at 1.5 and 4.6 T, and at temperatures from 2.1 to 41 K. These magnetic results may be fitted to a 'mean-field' model of magnetic exchange in which the total exchange integral parameter, ΣijJij, is c. -1.1 K. The magnetic results and structural details for the compound suggest that the strongest exchange pathway connects chains of alternating cations and anions. The inter-chain exchange is small. However, the substantial magnetic anisotropy and the much stronger decrease with temperature of the FeCl4- ion site moment, relative to that of the cation, both indicate a complex magnetic exchange network and consequent magnetic behaviour. No sign of magnetic order is observed to at least 2.9 K.

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Single-Crystal Magnetic Properties of [Co(NH3)5(OH2)] [Cr(CN)6] Between 2 and 300 K

Australian Journal of Chemistry ◽

10.1071/ch9921899 ◽

1992 ◽

Vol 45 (11) ◽

pp. 1899 ◽

Cited By ~ 1

Author(s):

PA Reynolds ◽

CD Delfs ◽

BN Figgis ◽

B Moubaraki ◽

KS Murray

Keyword(s):

Ising Model ◽

Field Model ◽

Mean Field ◽

Zero Field ◽

Spin Orbit Coupling ◽

Zero Field Splitting ◽

Magnetic Exchange Interaction ◽

Mean Field Model ◽

Magnetic Exchange ◽

The Mean

The magnetic susceptibilities along and perpendicular to the c axis (hexagonal setting) between 2.0 and 300 K at a magnetic field of 1.00 T, and the magnetizations at field strengths up to 5.00 T, are presented for single crystals of [Co(NH3)5(OH2)] [Cr(CN)6]. The results are interpreted in terms of zero-field splitting (2D) of the ground 4A2g term by spin-orbit coupling and of magnetic exchange interaction between the chromium atoms. The magnetic exchange is modelled as one of Ising or mean-field in type. The exchange is found to be quite small: J = -0.18(6) cm-1 if the Ising model is employed, and -0.03(1) cm-1 for the mean-field model. The model adopted for the exchange has a strong influence on the value of the parameter D obtained. When the Ising model is used D is deduced to be -0.28(9) cm-l; when the mean-field model is used D is -0.14(4) cm-l. The g-values deduced are in agreement with those from e.s.r. measurements at higher temperatures and do not depend on the exchange model. In any case, D is found to be sufficiently large that it must be considered in a polarized neutron diffraction experiment on the compound.

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Path Integral Method in the Mean-field Model for the Magnetic Vector Potential

Geomagnetism and Aeronomy ◽

10.1134/s0016793220070300 ◽

2020 ◽

Vol 60 (7) ◽

pp. 989-992

Author(s):

E. V. Yushkov ◽

C. R. Kamaletdinov ◽

D. D. Sokoloff

Keyword(s):

Path Integral ◽

Vector Potential ◽

Integral Method ◽

Field Model ◽

Mean Field ◽

Magnetic Vector Potential ◽

Magnetic Vector ◽

Mean Field Model ◽

The Mean ◽

Path Integral Method

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KDP-type crystal spontaneous polarization behavior better explained by bound charge semiconductor model than by mean field model

Ferroelectrics ◽

10.1080/00150193.2020.1791663 ◽

2020 ◽

Vol 569 (1) ◽

pp. 70-81

Author(s):

V. Hugo Schmidt

Keyword(s):

Spontaneous Polarization ◽

Field Model ◽

Mean Field ◽

Mean Field Model ◽

Polarization Behavior ◽

Type Crystal

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Quark mean-field model for single and double and hypernuclei

Progress of Theoretical and Experimental Physics ◽

10.1093/ptep/ptt119 ◽

2014 ◽

Vol 2014 (1) ◽

pp. 13D02-0 ◽

Cited By ~ 11

Author(s):

J. N. Hu ◽

A. Li ◽

H. Shen ◽

H. Toki

Keyword(s):

Field Model ◽

Mean Field ◽

Mean Field Model

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EVOLUTION OF SHELL STRUCTURE IN NUCLEI

International Journal of Modern Physics E ◽

10.1142/s0218301311019581 ◽

2011 ◽

Vol 20 (08) ◽

pp. 1663-1675 ◽

Cited By ~ 4

Author(s):

A. BHAGWAT ◽

Y. K. GAMBHIR

Keyword(s):

Shell Structure ◽

Crucial Role ◽

Field Model ◽

Mean Field ◽

Mass Region ◽

The Other ◽

Mean Field Model ◽

Relativistic Mean Field ◽

Shell Closures ◽

Low Mass

Systematic investigations of the pairing and two-neutron separation energies which play a crucial role in the evolution of shell structure in nuclei, are carried out within the framework of relativistic mean-field model. The shell closures are found to be robust, as expected, up to the lead region. New shell closures appear in low mass region. In the superheavy region, on the other hand, it is found that the shell closures are not as robust, and they depend on the particular combinations of neutron and proton numbers. Effect of deformation on the shell structure is found to be marginal.

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