A new hydrostatic medium for diamond anvil cells to 300 kbar pressure

We have shown that the rare gas xenon provides a hydrostatic medium for gasketed samples in a diamond anvil cell to pressures of 300 kbar. Previously, hydrostatic conditions were limited to ～100 kbar in a methanol-ethanol mixture. Three spectroscopic tests were used to determine that pressure gradients were small in the solidified gas. Since xenon has a convenient melting temperature, easy cell loading is possible. The small volume in the gasket requires only a few cm³ of gas. By analogy the other rare gases may be expected to show similar hydrostatic properties. Helium, for example, would be useful for X-ray studies.