computational approach was utilized to design the framework and to identify potential guest atoms for stabilizing nitrogen-substituted carbon and silicon clathrates. Two new series of N-substituted carbon and silicon clathrates compounds were discovered as potential candidate materials. One of the hybrid C\bond N clathrates was successfully synthesized using an industrial arc-melting technique. The theoretical bulk moduli of these N-substituted carbon and silicon clathrates were computed and they are comparable to those of C

3

N

4

Si

3

N

4

and SiC. Some N-substituted carbon clathrates may be suitable for application as hard materials.