This paper provides a concise, introductory review intended mainly for Mössbauer spectroscopy (MS) scientists not familiar with the most modern aspects of High Pressure (HP) methodology. Following a short introduction to the 1st generation HP-MS based on Drickamer's pressure cells, we describe the principles of the 2nd generation of HP-MS based on the Diamond Anvil Cell (DAC) including in-situ pressure measurements, the use of the high-specific activity 57Co(Rh) point sources, and examples of miniature DAC's. Finally, we present recent studies carried out with 57Fe HP-MS combined with other HP techniques such as resistivity, and synchrotron-based x-ray diffraction, describing unique cases of the breakdown of magnetism and the Mott transition in hematite (Fe2O3), pressure-induced spin crossover in Wüstite (FeO), pressure induced Fe 2+ → Fe3+ in Fe(OH)2, and (P,T) induced inverse↔ normal spinel transition in magnetite (Fe3O 4).
- Diamond-anvil cells
- Fe Mössbauer effect