Rare-earth metal catalysts for high-pressure synthesis of rare diamonds.

The combination of the unique properties of diamond and the prospects for its high-technology applications urges the search for new solvents-catalysts for the synthesis of diamonds with rare and unusual properties. Here we report the synthesis of diamond from melts of 15 rare-earth metals (REM) at 7.8 GPa and 1800-2100 °C.

Effect of Oxygen on Diamond Crystallization in Metal-Carbon Systems.

In this article, we report the influence of oxygen concentration in the transition-metal solvent-catalyst on the crystallization processes, morphology, and defect-and-impurity content of diamond crystals. In a series of experiments, the concentration of oxygen ( ) in the growth system was varied by adding FeO to the charge, and the other parameters and conditions of the growth were constant: NiFe solvent-catalyst, = 6.0 GPa, = 1400 °C, and duration of 40 h.