NBO(i) Type ED/e NBO(j) Type ED/e E(2)a (kJ/mol ) E (j)–E(i)b (a.u.) F (i, j)c (a.u.) C3-H15 σ 1.97986 N4-C5 σ* 0.01705 3.49 0.86 0.049 C7-C8 σ 1.97171 C7-C12 σ* 0.04047 3.52 1.25 0.059 π 1.66774 C9-C10 π* 0.34676 20.82 0.29 0,096 C7-C8 π 1.66774 C11-C12 π* 0.35284 19.05 0.29 0.066 C7-C12 σ 1.97135 C7-C8 σ* 0.02577 3.49 1.26 0.059 C8-C9 σ 1.97719 N1-C7 σ* 0.02984 3.97 1.12 0.060 C8-H22 σ 1.97632 C7-C12 σ* 0.04047 4.31 1.06 0.061 C9-C10 π 1.68511 C7-C8 π* 0.38418 19.12 0.28 0.066 π 1.68511 C11-C12 π* 0.35284 20.59 0.28 0.069 C9-H23 σ 1.97991 C7-C8 σ* 0.02577 4.17 1.08 0.060 C10-C11 σ 1.97596 C12-O26 σ* 0.02797 3.90 1.04 0.057 C10-H24 σ 1.98049 C8-C9 σ* 0.01457 3.79 1.10 0.058 C11-C12 π 1.68499 C7-C8 π* 0.38418 19.49 0.29 0.068 π 1.68499 C9-C10 π* 0.34676 18.78 0.29 0.067 C11-H25 σ 1.97663 C7-C12 σ* 0.04047 4.82 1.06 0.064 LP(1)N1 σ 1.82146 C2-H13 σ* 0.03654 8.83 0.64 0.070 σ 1.82146 C7-C8 π* 0.38418 16.13 0.30 0.065

aE (2) means energy of hyper conjugative interaction (stabilization energy); bEnergy difference between donor and acceptor i and j NBO orbitals; c F (i, j) is the Fork matrix element between i and j NBO orbitals.

Table 13: The Second-order perturbation energies E(2) (kJ/mol) corresponding to the most important charge transfer interactions (donor-acceptor) in MPP by B3LYP/6-311++G** method.