Ferromagnetism saturation magnetization

The values for the atomic saturation magnetization at the absolute zero, ferromagnetic metals iron, cobalt, and nickel are 2.22, 1.71, and 0.61 Bohr magnetons per atom, respectively.9 These numbers are the average numbers of unpaired electron spins in the metals (the approximation of the g factor to 2 found in gyromagnetic experiments shows that the orbital moment is nearly completely quenched, as in complex ions containing the transition elements). 

Figure 1. Schematic diagram of a hysteresis curve for a typical ferromagnet showing magnetization (a) as a function of the applied magnetic field (H) Saturation magnetization Is Indicated by Os- Inset shows the multidomain structure and subdomain superparamagnetlc clusters.

Hysteresis curves for a magnetically hard and a magnetically soft ferromagnetic material. S = saturation magnetization, R = remanent magnetization, K = coercive force... 

The spinel ferrites were fabricated by solid state reaction technique. Cobalt and Zinc ferrites CoxZnyFe204,(x=0.7,0.3,0.4,0.2 and y=0.3,0.7,0.6,0.8) were prepared by solid state reaction technique. The crystalline structure of the sample was investigated by X-ray diffraction(XRD). All samples show cubic spinel structure. The lattice parameter decreases with increasing cobalt content. Magnetic properties shows that the prepared sample exhibit ferromagnetic behaviour at room temperature. The saturation magnetization increases with increasing cobalt content. Curie temperature... 

In the preceding section, the magnetic field was mainly used to determine the saturation magnetization of ferromagnets. However, it is now well established that many actinide compounds have complex magnetic behaviour and the application of an external field may change or suppress antiferromagnetic structures. 

The density of CoNi powder decreases steadily in the 8.5-7.5 g cm-3 range as the mean particle size decreases from 300 to 50 nm. The saturation magnetization follows the same trend. It has been inferred from those measurements that the particles are formed by a metallic, ferromagnetic, nonporous core whose density is close to the bulk value (8.9 g cm-3). This core is coated by an impurity layer whose density and thickness are 4 g cm-3 and 2 nm, respectively.33... 

Values of the low-temperature saturation magnetic moment of ferromagnetic substances represent the maximum component of the atomic magnetic moment in the field direction for example, for spin alone the value in Bohr magnetons is 2S, whereas the magnetic moment obtained from the paramagnetic susceptibility is 2 /S(S + 1). 

---