Structure and Magnetic Properties of Li–Cu Ferrite

Abstract

Stress distribution and diamond phases in polycrystalline diamond film have been investigated by micro‐Raman spectroscopy. Intensity, lineshape and peak position of the diamond Raman line largely change on the film surface, particularly if grain center and grain boundary regions are compared. Whereas in the center of the grains the characteristic diamond Raman line is observed, close to grain boundaries an additional feature at 1326 cm—1 is detected. Such a Raman component may be related to the presence of hexagonal microphases formed by a defect‐induced symmetry modification of the diamond lattice. Grain boundaries appear also to be affected by a strongly anisotropic stress, which induces a frequency shift and splitting of the Raman peak. Stress configurations compatible with the experimental observations are proposed and discussed.

Magnetic Properties of Zn Substituted Cu Ferrite

“…This behavior was for all samples with 0.6 s  , while the samples with s > 0.6 showed a very low net magnetization. The present results agreed well with the results obtained earlier by other groups (8)(9)(10)(11)(12)(13)(14) .…”

“…This behavior of decrement is due to the further increase of H that causes a slight increase of B giving rise to distinct decrease in r  . This behavior is also observed for samples with s > 0.6 as shown in figure (8), where the samples have very low magnetization. Similar behavior was also found for Li -Cu and Cu -Ti samples (8,25) .…”

“…In the range of the applied magnetic field, H, under consideration(0 -510Am -1 ), the measured magnetization M of the samples do not reach a saturation of magnetization. The saturation of magnetization (8) of mixed Cu-Zn spinel ferrites at the absolute zero point would be expected to increase with increase of the  2 Zn ions. Thus, the remarkable fact appears that, the substitution of the magnetic ions in a ferrimagnetic materials by the non-magnetic ions such as…”

Cation ordering and order–disorder phase transitionin Co-substituted Li4Ti5O12 spinels

“…The occupancy ratio of the Wyckoff's positions of cations in the A/B sublattice is entitled "type of ordering". These spinels become disordered (S.G. Fd3m) by a cation substitution and/or by a thermal treatment (heating or cooling) [8,9]. Ternary samples Li1.33xCo2−2xTi1+0.67xO4 (0 < x < 1) were obtained by a partial cation substitution, Li + + Ti 4+ → 5/2 Co 2+ in the parent diamagnetic compound Li4Ti5O12.…”

<title>Infrared absorption and dielectric properties of Li-Cu ferrite</title>

“…This value represents the contribution of the ionic bond Fe-O in the lattice.Since, Li ions and more than 90% of Cu2 ions exist in B-sites according to the cation distribution[19]: It is clear that no change in 'A with composition but 'B increases with increasing Cu content.…”