Theory of the gasket in diamond anvil high-pressure cells

The operation of the gasket in the diamond anvil cell (DAC) is analyzed and some practical conclusions are given, relevant to users of DACs in the submegabar pressure range. Two distinct regimes are found, one where the gasket is at the maximum thickness and the DAC is intrinsically unstable, and the other where the gasket is thin and the cell is stable in operation, so that there are good reasons to use preindented gaskets, of thickness rather less than usually recommended. Force-pressure plots are shown to give valuable information in routine use, and their interpretation is discussed.