X-ray diffraction under ultrahigh pressure generated with sintered diamond anvils

High pressures generated with sintered diamond as the second stage anvils in the ‘‘6-2 type’’ double-stage apparatus have been calibrated by x-ray diffraction with synchrotron radiation. Sintered diamond has permitted a fair amount of x-ray transparency although the chemical analysis shows the existence of 14-wt. % Co binder. Anvils with a top face of 0.7 mm diam performed the generation of 60 GPa, which was confirmed on the lattice parameters of B1 and B2 phases of NaCl. No appreciable plastic deformation of the used anvils has certified the higher pressure generation.