Phosphor imaging plates are currently used. An X-ray exposure can last as long as several hours to ensure good counting statistics. The diamond anvil cell and the high pressure scale Two opposed high-quality diamonds pressing against a sample constrained by a metallic foil, acting as a deforming gasket, constitute the core of the diamond anvil high pressure cell or DAC for short. Due to the small sample volume, a sine qua non condition to reach high pressures, the use of the high photon flux provided by synchrotron radiation at short wavelength is imperative. The DAC is also well suited for other physical characterization methods, e.g., luminescence, absorption, vibrational and M ssbauer spectroscopy, and electrical transport and magnetic measurements.
Intense spots arise from Bragg reflections from the single crystal diamonds.
At high pressure, both dioxides follow the same structural phase transitions over the same pressure range. The similarity between the two dioxides is normally attributed to the lanthanide contraction which gives rise to the fact that Zr and Hf have equivalent sizes. In addition to similar phase diagrams, we could, for both dioxides, quench to room conditions a high-density phase occurring at pressures in excess of 30 GPa. The retrieved materials, according to the EDXD data, presented a high density and seemed to have a low compressibility. These observations could only be inferred by first determining the crystalline structure of the retrieved materials to calculate correctly both the density and the bulk modulus.