Related Experiment Video
Updated: May 31, 2026
Methods of Ex Situ and In Situ Investigations of Structural Transformations: The Case of Crystallization of Metallic Glasses
Published on: June 7, 2018
Phase coexistence and metastability in polycrystalline Pr(0.2)La(0.8)Fe(11.4)Al(1.6) compound
1State Key Laboratory of Magnetism, Institute of Physics and Centre for Condensed Matter Physics, Chinese Academy of Sciences, Beijing 100080, People's Republic of China.
Abstract:
Electrical resistivity, dc magnetization, ac magnetic susceptibility, and magnetic relaxation studies of polycrystalline Pr(0.2)La(0.8)Fe(11.4)Al(1.6) compound have been carried out. On the basis of the measurements of isofield magnetization and ac magnetic susceptibility, we provide evidence for phase coexistence (the appearance of the ferromagnetic phase in the antiferromagnetic matrix) rather than a spin glass, resulting in a cusp observed at ∼70 K in the zero-field-cooled thermal magnetization curve under low fields. The ferromagnetic clusters or nuclei appear randomly in the antiferromagnetic matrix according to the electrical resistivity results. An excellent magnetic-resistive correspondence is observed under medium fields. Under these fields large relaxation effects are presented in the vicinity of the phase transition temperature. Nonuniform variation of the relaxation rate with temperature gives a clear picture of the nucleation and growth of phases. Distinct metastable behavior is shown during the phase transition, which brings about the step-like behavior in the various magnetization curves.
Related Concept Videos
02:37Metallic Solids
All metallic solids exhibit high thermal and electrical conductivity, metallic luster, and malleability. Many...
01:29Imperfections in Crystal Structure: Non-Stoichiometric Defects
03:02Colors and Magnetism
When atoms or molecules absorb light at the proper frequency, their electrons are excited to higher-energy orbitals. For many main group atoms and molecules, the absorbed photons are in the ultraviolet range of the electromagnetic spectrum, which cannot be detected by the human eye. For coordination compounds, the energy difference between the d orbitals often allows photons in the visible range to be absorbed and emitted, which is seen as colors by the human eye.
01:26Imperfections in Crystal Structure: Stoichiometric Point Defects
01:21Polymer Classification: Crystallinity
Crystalline domains are the regions where polymer chains are aligned in an orderly manner and held together in proximity by intermolecular forces. For example, chains in the crystalline domains of polyethylene and nylon are bound together by van der Waals...
02:58Crystal Field Theory - Octahedral Complexes
To explain the observed behavior of transition metal complexes (such as colors), a model involving electrostatic interactions between the electrons from the ligands and the electrons in the unhybridized d orbitals of the central metal atom has been developed. This electrostatic model is crystal field theory (CFT). It helps to understand, interpret, and predict the colors, magnetic behavior, and some structures of coordination compounds of transition metals.
CFT focuses on...