ELECTRONIC STRUCTURE OF SIX PHASES OF C3N4: A THEORETICAL APPROACH

A systematic study of the structural properties and electronic structure of six phases of C 3 N 4 is presented. The phases under study are the β, α, cubic, pseudocubic and two graphitic with different space group. The structural analysis shows that only in β and graphitic phases the N atoms behave in a pure sp 2 configuration. In the other phases, α, cubic and pseudocubic, the N with its 3 C neighbors form a pyramid. The band structure for each of the six phases is presented indicating with β, α and cubic phases have an indirect gap while the pseudocubic and the two graphitic phases have a direct gap. Also charge density contours are presented and analyzed.