High pressure synthesis of new heterodiamond phase

New heterodiamond phase (structure type of cubic boron nitride) with boron and nitrogen atoms partially substituted by carbon has been synthesized by using high pressure-high temperature treatment of the mixture of boron and C3N4 carbon nitride powders. This phase consisted of up to 5 micron-sized individual crystals. The composition of new phase was established with the help of microanalysis and structure refinement.