DAC experiments allow various materials to be held at the static pressures found deep in planetary interiors, and their popularity is in part due to their ease of use. Samples can be heated to extreme temperatures and allow are amenable to a huge range of analytical techniques. DAC experiments have found particular popularity in the Earth and planetary sciences, as well as in materials sciences, chemistry, and biological materials. Measurements can be made through the diamond anvils, either optically or using a synchrotron X-ray source, and additional measurements can be made after the experiment by extracting the sample. The main limitations of DAC experiments are the very small sample size and the high potential for heterogeneous heating and diffusion. Using just XRD for a laser-heated experiment could miss important features such as disequilibrium and diffusion. By combining in-situ and ex-situ techniques, experimental products can be fully characterised. An ideal case could consist of in-situ XRD to identify the high-PT phases, confirm PT conditions and to refine equation of state; followed by ex-situ micro- and nanoscale imaging and compositional measurements, to relate XRD measurements to experimental textures and to characterise phase compositions and elemental distribution within the DAC experiment.
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