The replacement of one C2 by N, leading to Si 2 C 2 N 2 equiatomic compound, results in a differentiated charge envelop along the C-N pairs with the largest charge volume around N (Fig. ). These results are chemically sound is so far that they go along with the electronegativity trends: χ(N) = 3.04 > χ(C) = 2.55 > χ(Si) = 1.80 which coincide with the trends of charge transfers from Si to both C and N, i.e. δ(N) = -2.12, δ(C) = -1.72, and δ(Si) = +3.84.