Paramagnetic resonance studies of phase transitions in condensed materials

Magnetic properties in BaFe12O19 nanoparticles prepared under a magnetic field

“…It is suggested that the quadrupole-spit doublets component is due to the inherent randomness in site occupancy of different ions, the presence of cation vacancies and especially a fraction of finer particles in the superparamagnetic range, which results in no proper magnetic interactions to show a magnetic hyperfine splitting. For the particles below the critical size, thermally induced energy fluctuations can overcome the anisotropy energy and change the direction of the magnetization of a particle from one easy axis to another [26]. In Table 1, however, the parameters of two spectra have an ossbauer spectra recorded at room temperature for ZF and AF samples.…”

Evidence for magnetic ordering in ultrathin gadolinium Langmuir-Blodgett films

“…24,25 In bulk magnets, below the ordering temperature (T 0 ) the intensity of the nonshifted EPR line decreases 10 and the signal becomes very small. 24 This results from a shifting of the intrinsic EPR signal to low fields in ferromagnets and to rather high fields in antiferromagnets.…”

Carbon covered magnetic nickel nanoparticles embedded in PBT-PTMO polymer: Preparation and magnetic properties

“…5). This type of behavior is often observed in magnetic resonance spectra of nanoparticles in a low temperature range [2,[20][21][22]. It has been proposed that a spin-glass-like surface layer on a nanoparticle undergoes a magnetic transition to a frozen state at the spin-freezing temperature T g .…”