Magnetization Density in an Iron(III) Magnetic Cluster. A Polarized Neutron Investigation

1999 ◽  
Vol 121 (22) ◽  
pp. 5342-5343 ◽  
Author(s):  
Yves Pontillon ◽  
Andrea Caneschi ◽  
Dante Gatteschi ◽  
Roberta Sessoli ◽  
Eric Ressouche ◽  
...  
Keyword(s):  
Magnetic Cluster ◽  
Magnetization Density ◽  
Cluster A ◽  
Polarized Neutron

Magnetic Order of Co0.1Pt0.9 in Proximity of CoPt3

1998 ◽  
Vol 517 ◽  
Author(s):  
A.L. Shapiro ◽  
F. Hellman ◽  
M.R. Fitzsimmons
Keyword(s):  
Depth Profile ◽  
Magnetic Order ◽  
Neutron Reflectometry ◽  
Bilayer Film ◽  
Ferromagnetic Order ◽  
Magnetization Density ◽  
Close Proximity ◽  
Polarized Neutron ◽  
The Moment ◽  
Polarized Neutron Reflectometry

AbstractA polarized neutron reflectometry study of the magnetization density depth profile of a Co0.1Pt0.9-CoPt3 bilayer film found evidence for an induced moment in the Co0.1Pt0.9 overlayer in close proximity to the CoPt3 underlayer. If the moment of Co in these films is that of the bulk, then the μpt = 0.09(1)μB in the overlayer, and μpt = 0.04(1)μB, in the underlayer. In addition, ferromagnetic order of the Co0.1Pt0.9 overlayer was observed 8K above Tc for the material in the bulk.

Magnetization density in a Mn high-spin (S = 12) magnetic cluster

1997 ◽  
Vol 241-243 ◽  
pp. 600-602 ◽  
Author(s):  
A Caneschi ◽  
D Gatteschi ◽  
R Sessoli ◽  
J Schweizer
Keyword(s):  
High Spin ◽  
Magnetic Cluster ◽  
Magnetization Density

Magnetization densities and electronic states in crystals

1980 ◽  
Vol 290 (1043) ◽  
pp. 481-495 ◽  
Keyword(s):  
Neutron Technique ◽  
Magnetic Scattering ◽  
Magnetization Distribution ◽  
Crystalline Materials ◽  
Magnetic Elements ◽  
Magnetization Density ◽  
Valence Electrons ◽  
Polarized Neutron ◽  
Insight Into

The classical polarized neutron technique provides an extremely sensitive method for studying magnetization distributions in crystalline materials. In the transition metals and their compounds it is recognized that the d electrons act both as valence electrons and as carriers of the magnetism. This dual role implies that the magnetization distribution can give information about the behaviour of valence electrons. The pioneering work in this field yielded new insight into the behaviour of the magnetic elements themselves. The paper begins with an introduction to the elastic magnetic scattering of neutrons, the electronic origin of magnetization density and the polarized neutron technique itself. A brief survey of earlier work in the important areas of application is followed by more detailed discussion of three recent experiments: the determination of the paramagnetic form factor of technetium, a study of orbital effects in a ferrimagnetic vanadium salt (K 5 V 3 F 14 ) and the spin density and bonding in the [CoCl 4 ] 2- ion.

Polarized neutron study of the magnetization density in La 0.8 Sr 0.2 MnO 3

1998 ◽  
Vol 42 (1) ◽  
pp. 85-90 ◽  
Author(s):  
J Pierre ◽  
B Gillon ◽  
L Pinsard ◽  
A Revcolevschi
Keyword(s):  
Magnetization Density ◽  
Polarized Neutron

The magnetization density of hexacyanoferrate(III) ion measured by polarized neutron diffraction in Cs 2 KFe(CN) 6

1988 ◽  
Vol 419 (1857) ◽  
pp. 205-219 ◽  
Keyword(s):  
Neutron Diffraction ◽  
Iron Atom ◽  
Theoretical Calculations ◽  
Electronic Configuration ◽  
Dipole Approximation ◽  
Ligand Field ◽  
Cubic Symmetry ◽  
Structure Factors ◽  
Magnetization Density ◽  
Polarized Neutron

A polarized neutron diffraction experiment on Cs 2 KFe(CN) 6 gave 292 unique magnetic structure factors. These were analysed by using a model for the magnetization density of multipoles and valence functions on the iron and ligand atoms, with the dipole approximation for orbital effects. Neither the ligand nor the iron atom densities retain the cubic symmetry of the free ferricyanide ion. The natural axes of quantization of the iron atom are rotated by significant amounts from the Fe-CN vectors. The iron electronic configuration was found to be d -0.64(8) xy d 0.78(6) xz d 0.72(5) yz d -0.06(6) z 2 d 0.17(7) x 2 - y 2 corresponding to the cubic t 5 2g configuration of the low-spin d 5 Fe III ion perturbed to put all spin in the d xz and d yz orbitals. The negative spin in the d xy orbital and the 6% of negative spin on the carbon atoms conform with the qualitative predictions of previous ab initio theoretical calculations, although for d xy there are large manifestations of spin polarization. The 12% of spin delocalized onto nitrogen atoms reflects covalence. The ligand populations depart considerably from those for cubic symmetry, and can be understood in terms of spin occupation of molecular orbitals involving 3d-t 2g orbitals with coefficients d xy < d xz < d yz . These observations can be rationalized by an empirical model in which the ligand field components exerted by the cyanide groups are influenced by details of the crystal structure.

scholarly journals Polarized-neutron-diffraction study of the magnetization density in hexagonalY2Fe17

1994 ◽  
Vol 50 (13) ◽  
pp. 9293-9299 ◽  
Author(s):  
O. Moze ◽  
R. Caciuffo ◽  
B. Gillon ◽  
G. Calestani ◽  
F. E. Kayzel ◽  
...  
Keyword(s):  
Neutron Diffraction ◽  
Diffraction Study ◽  
Neutron Diffraction Study ◽  
Magnetization Density ◽  
Polarized Neutron

Polarized neutron diffraction study of the magnetization density distribution in Rb 2 CrCl 4 : a two-dimensional ionic ferromagnet

1986 ◽  
Vol 406 (1830) ◽  
pp. 39-61 ◽  
Keyword(s):  
Neutron Diffraction ◽  
Density Distribution ◽  
Neutron Diffraction Study ◽  
Orbital Ordering ◽  
Teller Distortion ◽  
Main Structure ◽  
Magnetization Density ◽  
Jahn Teller ◽  
Polarized Neutron ◽  
Secondary Extinction

The magnetization density distribution in the ionic ferromagnet Rb 2 CrCl 4 has been determined by polarized neutron diffraction from a single crystal at 4.5 K. Magnetic structure factors F M were derived from the flipping ratios R of 660 main structure reflections (189 independent) and 57 super-structure reflections with sin θ /λ ≼ 0.8 Å -1 (λ = 0.90 Å). The main structure reflections were corrected for extinction using a secondary extinction parameter. The F M were modelled by representing the mag­netization density by a superposition of densities from orbitals centred at each atom : Cr(3d, 4s) and Cl(3s, 3p). The results verify the presence of orbital ordering arising from the cooperative Jahn-Teller distortion in the basal plane, previously postulated as responsible for the ferromagnetic exchange interaction. The proportion of the Cr 2+ moment occupying each 3d orbital is 0.26(2)( yz ), 0.25(2)( xz ), 0.25 0.25(2)( z 2 ) and — 0.01 (2)( x 2 — y 2 ), where z is the principal axis of Jahn-Teller elongation at each Cr site. The optimum refined distribution of the magnetic moment (μ B ) was Cr(3d) 3.16(8), Cr(4s) 0.6(1), equatorial Cl(3s) 0.05(2), Cl(3p) 0.06(3) and axial Cl(3s) 0.03(3), Cl(3p) 0.08(5).

Sign in / Sign up

Export Citation Format

Share Document