Structure of Unhydrogenated Amorphous Silicon Carbide

Simulations of unhydrogenated amorphous silicon carbide, formed by condensing a vapor of silicon and carbon atoms, indicate partial chemical ordering, with heteronuclear bonds predominating. We find no evidence of phase separation. Carbon atoms are predominantly three-fold coordinated while silicon atoms have four-fold coordination. By combining these results with results of experimental studies, we speculate on the role of hydrogenation in determining the structure of amorphous silicon carbide.