Atomic-Scale Properties of Structure, Valence, and Magnetism in Pressure-Induced Amorphized Materials

The atomic-scale features of pressure-induced amorphized material are described for selected materials. Mossbauer spectroscopy parameters such as hyperfine magnetic and quadrupole interactions, isomer shift, spectral intensities, and f-values are applied in 57Fe, 119Sn and l29I nuclei to elucidate features of the disordered phase such as changes in coordination number, density, relative abundance in the coexisting pressure range, magnetic features, and local-ordering. Those findings are supplemented by IR, Raman, X-ray spectroscopy, and X-ray diffraction. The materials discussed are some of the AB4 molecular crystals, the antiferromagnetic four-fold coordinated FePO4 and Fe2SiO4, and some preliminary data on the layer structured Fe(OH)2. [Mossbauer spectroscopy, high pressure, amorphization, structure, magnetism].