High-brilliance X-ray system for high-pressure in-house research: applications for studies of superhard materials

Abstract

Newly installed, at Bayerisches Geoinstitut, X-ray system consists of three major components: RIGAKU FR-D high-brilliance source, Osmic's Confocal Max-Flux optics, and SMART APEX 4K CCD area detector. We tested the system for single-crystal structural studies on example of garnet, Co₃Al₂Si₃O₁₂, for powder diffraction analysis on example of a small sample of boron carbide, B₄C, recovered after treatment in a multi-anvil apparatus, and for in situ experiments at high pressure on example of FeO compressed in a diamond anvil cell to>100 GPa. In all the cases, the system demonstrated its reliability and provided results comparable with those obtained using the best currently available instruments. Using a new X-ray system, we measured the compressibility of superhard nanocrystalline diamond at pressures up to 26 GPa and found it to be extremely incompressible with K _T=488(4) GPa, K′=3.1(2), and V ₀=3.401(6) cm³/mol.

Keywords:

• In-house X-ray
• DAC
• Nanodiamond

Acknowledgements

L.D. thanks Deutsche Forschungsgemeinschaft (DFG) for financial support.