The negative values of J1and J2 indicate the existence of
antiferromagnetic coupling between Mn(II) ions.
Our open-end coaxial probe measurements at the end of the paper attempt to observe the weak ferromagnetic resonance due to spin canting seen particularly in
antiferromagnetic resonance investigations on crystalline [alpha]-[Fe.sub.2][O.sub.3], also known as the mineral hematite (6), (8).
Magnetic coupling occurs because of super exchange interactions between the spin clusters and small
antiferromagnetic coupling within the cluster.
Observed Mn-O distances at 2 K compared against the expected distortions for each of the three low temperature magnetic perovskite phases in ([Pr.sub.0.35][Y.sub.0.07][Th.sub.0.04][Ca.sub.0.04] [Sr.sub.0.5])Mn[O.sub.3] Observed Mn-O Phase Expected Mn[O.sub.6] distances (and properties) octahedral geometry ([Angstrom]) F type Regular 1.936(1) X 4 (ferromagnetic, metallic) 1.936(1) X 2 A type Tetragonal compression 1.901(1) X 2 (
antiferromagnetic, 1.948(1) X 4 2-dimensional conductor) CE type [Mn.sup.3+] site (a): 1.900(3) X 2 (charge ordered, tetragonal elongation 1.925(5) X 2
antiferromagnetic 2.056(6) X 2 insulator) [Mn.sup.4+] site (a): 1.907(1) X 2 regular 1.916(1) X 2 1.919(1) X 2 (a) The refinement was constrained to preserve the centres of symmetry of these octahedra.
However, there are other examples, like iron trithiohypophosphate (FePS3), which remarkably keeps its
antiferromagnetic ordering intact all the way down to monolayer.
There is a spin cyclical order with a period of 64 nm which is superimposed on this
antiferromagnetic order.
RuCl3 were well modelled by a series of magnetic interactions that were clearly dominated by the anisotropic Kitaev ferromagnetic interaction and an off-diagonal isotropic
antiferromagnetic interaction.
A wide application of materials containing nanosized
antiferromagnetic particles in different branches of nanotechnology is primarily due to a number of specific structural, magnetic, and thermodynamic properties of these materials found within long-term fundamental studies.
However, one limitation to the synthesis of metal nanoparticles is their reactivity toward air environment, which may degrade their ferromagnetic character by forming an
antiferromagnetic oxide layer.
Carpenter, "Co[F.sub.2]: A model system for magnetoelastic coupling and elastic softening mechanisms associated with paramagnetic [left and right arrow]
antiferromagnetic phase transitions," Journal of Physics: Condensed Matter, vol.
They are classified as ferrimagnetics with both ferromagnetic (FM) and
antiferromagnetic (AF) coupling between atomic moments, and the magnetic coupling depends on the specific crystallographic position of Fe ions [4].
In the case of HTSC, it has been demonstrated that the
antiferromagnetic (AF) and superconducting (SC) phases d-wave [1-4] and p-wave [5] superconductors can be given a unified explanation in terms of a nonlinear sigma model for a field which behaves as a vector transformation under SO(5) rotations.