Relative stability and electronic properties of group IV phosphides and nitrides

The structures and electronic properties of binary alloys C3N4 and C3P4 were examined closely using first principles method based on the density functional theory and the local density approximation. Our calculations revealed that electronegativity plays a dominant role in determining the electronic properties of these compounds. Different crystal structures are preferred by the nitride and phosphide because of the different bonding preferences of nitrogen and phosphorus. The relative stability of these two phases changes gradually with composition in the ternary alloy C3N4−nPn, but the electronic properties change drastically in the presence of phosphorus. Other group IV phosphides and nitrides show similar properties and trends, except some deviations by Sn3N4 and Sn3P4.