The magnetic structure of braunite Mn2+Mn3+6O8/SiO4

1998 ◽  
Vol 213 (1) ◽  
Author(s):  
S. Ohmann ◽  
I. Abs-Wurmbach ◽  
N. Stüßer ◽  
T. M. Sabine ◽  
K. Westerholt
Keyword(s):  
Neutron Diffraction ◽  
Magnetic Structure ◽  
Powder Diffraction ◽  
Diffraction Data ◽  
Magnetic Moments ◽  
Magnetic Ordering ◽  
Neutron Powder Diffraction ◽  
Powder Diffraction Data ◽  
Neutron Powder Diffraction Data ◽  
Weakly Coupled

AbstractNeutron powder diffraction data of braunite MnThe magnetic structure is dominated by the magnetic ordering of the A layers thus reflecting the relations of the chemical cell: Within the (001) plane of the A sheets magnetic moments of the two nonequivalent MnMagnetization experiments indicate that besides the afordered Mn ions weakly coupled spins ordering at temperatures below 2 K exist. In accordance with that, additional neutron diffraction reflections arise at

A Study of the Magnetic Structure of LaMn2O5from Neutron Powder Diffraction Data

2005 ◽  
Vol 2005 (4) ◽  
pp. 685-691 ◽  
Author(s):  
Angel Muñoz ◽  
Jose A. Alonso ◽  
María T. Casais ◽  
María J. Martínez-Lope ◽  
Jose L. Martínez ◽  
...  
Keyword(s):  
Magnetic Structure ◽  
Powder Diffraction ◽  
Diffraction Data ◽  
Neutron Powder Diffraction ◽  
Powder Diffraction Data ◽  
Neutron Powder Diffraction Data

A Study of the Magnetic Structure of LaMn2O5 from Neutron Powder Diffraction Data.

ChemInform ◽  
2005 ◽  
Vol 36 (17) ◽  
Author(s):  
Angel Munoz ◽  
Jose A. Alonso ◽  
Maria T. Casais ◽  
Maria J. Martinez-Lope ◽  
Jose L. Martinez ◽  
...  
Keyword(s):  
Magnetic Structure ◽  
Powder Diffraction ◽  
Diffraction Data ◽  
Neutron Powder Diffraction ◽  
Powder Diffraction Data ◽  
Neutron Powder Diffraction Data

ChemInform Abstract: Evolution of the Magnetic Structure of Hexagonal HoMnO3 from Neutron Powder Diffraction Data.

ChemInform ◽  
2010 ◽  
Vol 32 (35) ◽  
pp. no-no
Author(s):  
A. Munoz ◽  
J. A. Alonso ◽  
M. J. Martinez-Lope ◽  
M. T. Casais ◽  
J. L. Martinez ◽  
...  
Keyword(s):  
Magnetic Structure ◽  
Powder Diffraction ◽  
Diffraction Data ◽  
Neutron Powder Diffraction ◽  
Powder Diffraction Data ◽  
Neutron Powder Diffraction Data

scholarly journals Structure and magnetic properties of W-type hexaferrites

IUCrJ ◽  
2019 ◽  
Vol 6 (3) ◽  
pp. 492-499
Author(s):  
Mathias I. Mørch ◽  
Jakob V. Ahlburg ◽  
Matilde Saura-Múzquiz ◽  
Anna Z. Eikeland ◽  
Mogens Christensen
Keyword(s):  
Powder Diffraction ◽  
Diffraction Data ◽  
Spontaneous Magnetization ◽  
Magnetic Moments ◽  
Neutron Powder Diffraction ◽  
Magnetic Characteristics ◽  
Powder Diffraction Data ◽  
Hard Magnetic Materials ◽  
Neutron Powder Diffraction Data ◽  
Substitution Degree

W-type hexaferrites (WHFs) (SrMe 2Fe16O27, Me = Mg, Co, Ni and Zn) are hard magnetic materials with high potential for permanent magnet applications owing to their large crystalline anisotropy and high cation tunability. However, little is known with regards to their complex structural and magnetic characteristics. Here, the substitution of metals (Me = Mg, Co, Ni and Zn) in WHFs is described and their crystal and magnetic structures investigated. From joined refinements of X-ray and neutron powder diffraction data, the atomic positions of the Me atoms were extracted along with the magnetic dipolar moment of the individual sites. The four types of WHFs exhibit ferrimagnetic ordering. For Mg, Ni and Zn the magnetic moments are found to be ordered colinearly and with the magnetic easy axis along the crystallographic c axis. In SrCo2Fe16O27, however, the spontaneous magnetization changes from uniaxial to planar, with the moments aligning in the crystallographic ab plane. Macromagnetic properties were measured using a vibration sample magnetometer. The measured saturation magnetization (M s) between the different samples follows the same trend as the calculated M s extracted from the refined magnetic moments of the neutron powder diffraction data. Given the correlation between the calculated M s and the refined substitution degree of the different Me in specific crystallographic sites, the agreement between the measured and calculated M s values consolidates the robustness of the structural and magnetic Rietveld model.

Evolution of the Magnetic Structure of Hexagonal HoMnO3from Neutron Powder Diffraction Data

2001 ◽  
Vol 13 (5) ◽  
pp. 1497-1505 ◽  
Author(s):  
A. Muñoz ◽  
J. A. Alonso ◽  
M. J. Martínez-Lope ◽  
M. T. Casáis ◽  
J. L. Martínez ◽  
...  
Keyword(s):  
Magnetic Structure ◽  
Powder Diffraction ◽  
Diffraction Data ◽  
Neutron Powder Diffraction ◽  
Powder Diffraction Data ◽  
Neutron Powder Diffraction Data

The magnetic structure of α-MnMoO4

1994 ◽  
Vol 209 (12) ◽  
Author(s):  
G. Lautenschläger ◽  
H. Weitzel ◽  
H. Fuess ◽  
E. Ressouche
Keyword(s):  
Magnetic Structure ◽  
Powder Diffraction ◽  
Diffraction Data ◽  
Neutron Powder Diffraction ◽  
Powder Diffraction Data ◽  
Neutron Powder Diffraction Data

AbstractNeutron powder diffraction data of

Magnetic structure of hexagonalRMnO3(R=Y, Sc):Thermal evolution from neutron powder diffraction data

2000 ◽  
Vol 62 (14) ◽  
pp. 9498-9510 ◽  
Author(s):  
A. Muñoz ◽  
J. A. Alonso ◽  
M. J. Martínez-Lope ◽  
M. T. Casáis ◽  
J. L. Martínez ◽  
...  
Keyword(s):  
Magnetic Structure ◽  
Powder Diffraction ◽  
Diffraction Data ◽  
Thermal Evolution ◽  
Neutron Powder Diffraction ◽  
Powder Diffraction Data ◽  
Neutron Powder Diffraction Data

A perdeuterated cryoprotectant for neutron studies and a demonstration of its use for neutron powder diffraction onL-(−)-ephedrine hemihydrate

2001 ◽  
Vol 34 (2) ◽  
pp. 203-207 ◽  
Author(s):  
Frederik C. Krebs ◽  
Mikkel Jørgensen ◽  
Bente Lebech ◽  
Karla Frydenvang
Keyword(s):  
Neutron Diffraction ◽  
Powder Diffraction ◽  
Diffraction Data ◽  
Molecular Crystals ◽  
Neutron Powder Diffraction ◽  
Powder Diffraction Data ◽  
Organic Solids ◽  
Neutron Powder Diffraction Data

The use of perdeuteropolyethylpropylene (d-PEP) as a cryoprotectant for neutron studies of molecular organic solids is demonstrated by the solution of the structure of L-(−)-ephedrine hemihydrate from neutron powder diffraction data on a sample containing 20 wt% d-PEP. It is demonstrated that no contribution from d-PEP to the scattering is observed. Neutron diffraction studies of solvent-containing molecular crystals that require a perdeuterated cryoprotectant oil are thus possible.

Determination and Rietveld refinement of the crystal structure of Li0.50Ni0.25TiO(PO4) from powder X-ray and neutron diffraction

2002 ◽  
Vol 17 (4) ◽  
pp. 290-294 ◽  
Author(s):  
B. Manoun ◽  
A. El Jazouli ◽  
P. Gravereau ◽  
J. P. Chaminade ◽  
F. Bouree
Keyword(s):  
Crystal Structure ◽  
Neutron Diffraction ◽  
Powder Diffraction ◽  
Diffraction Data ◽  
Rietveld Method ◽  
Neutron Powder Diffraction ◽  
Powder Diffraction Data ◽  
X Ray ◽  
Neutron Powder Diffraction Data ◽  
Monoclinic Cell

The structure of the oxyphosphate Li0.50Ni0.25TiO(PO4) has been determined from conventional X-ray and neutron powder diffraction data. The parameters of the monoclinic cell (space group P21/c, Z=4), obtained from X-ray results, are: a=6.3954(6) Å, b=7.2599(6) Å, c=7.3700(5) Å, and β=90.266(6)°; those resulting from neutron study are: a=6.3906(7) Å, b=7.2568(7) Å, c=7.3673(9) Å, and β=90.234(7)°. Refinement by the Rietveld method using whole profile, leads to satisfactory reliability factors: cRwp=0.128, cRp=0.100, and RB=0.038 for X-ray and cRwp=0.110, cRp=0.120, and RB=0.060 for neutrons. The structure of Li0.50Ni0.25TiO(PO4) can be described as a TiOPO4 framework constituted by chains of tilted corner-sharing TiO6 octahedra running parallel to the c axis and cross linked by phosphate tetrahedra. In this framework, there are octahedral cavities occupied by Li and Ni atoms: Li occupies the totality of the 2a sites and Ni occupies statistically half of the 2b sites. Ti atoms are displaced from the center of octahedra units in alternating long (2.242 Å) and short (1.711 Å) Ti–O bonds along chains.

Sign in / Sign up

Export Citation Format

Share Document