Table 1. Sample-chamber parameters for various pressure ranges.

These parameters are designed for the condition of using a pair of wide-perforated Boehler anvils, together with a methanol:ethanol 4:1 mixture as the pressure medium. Pressure is expected to be increased only at low temperature (typically no higher than 25 K) using a helium diaphragm, in order to reduce the thermal expansion of the pressure medium and any thermal weakening of the gasket strength. The pressure is calibrated by the equation of state for silver (Ag) at T = 4 K using two parameters (bulk modulus B = 108.85 GPa, and B′ = dB/dP = 5.7).

Diamond culet size (µm)	Gasket materials	Initial shim thickness (µm)	Pre-indented thickness (µm)	Hole diameter (µm)	Targeted pressure (GPa)
800	Stainless Steel 301	305	162	390	18
700	Rhenium	255	156	330	25
600	Rhenium	255	141	280	35
550	Rhenium	255	121	240	42