Affiliation:
1. Sobolev Institute of Geology and Mineralogy, Siberian Branch of the Russian Academy of Sciences
Abstract
Based on the analysis of the results on the synthesis and growth of diamonds in metal-sulfide melts at high pressure, the reason for the crystallization of low-nitrogen diamond crystals is substantiated. The introduction of sulfur into the iron melt leads to a decrease in the solubility of nitrogen, which, in turn, leads to a decrease in the content of nitrogen atoms in the melt and the probability of their capture by growing diamond crystals in the form of a structural impurity. The addition of nickel lowers the melting point of the growth system, increases the amount of melt, and, accordingly, promotes the dissociation of molecular nitrogen into individual atoms, which are captured by diamonds during growth as a structural impurity.
Publisher
The Russian Academy of Sciences