This trend means that, surface reactivity of the NC6 and NC8 models of the zigzag BC3NT detect more changes with respect to the NB7 due to the nitrogen impurity.In the NB7 model, where one B atom is replaced by a single N atom, the negative regions associated with the carbon atoms are stronger than before, 13.2 vs. 11.8 kcal/mol, while the positive ones of the inner surfaces are notably weaker.