A B3LYP and MP2(full) theoretical investigation into explosive sensitivity upon the formation of the intermolecular hydrogen-bonding interaction between the nitro group of RNO2 (R = –CH3, –NH2, –OCH3) and HF, HCl or HBr

The change of the bond dissociation energy in the trigger bond (C–NO2, N–NO2 or O–NO2) upon the formation of the intermolecular hydrogen-bonding interaction between the nitro group of RNO2 (R = –CH3, –NH2, –OCH3) and HF, HCl or HBr have been investigated using the B3LYP and MP2(full) methods with the 6-311++G**, 6-311++G(2d,p) and aug-cc-pVTZ basis sets. The bond dissociation energy (BDE) is increased and the charge of nitro group turns more negative in complex in comparison with those in monomer. The increment (ΔBDE) correlates with the intermolecular hydrogen-bonding interaction energy. Furthermore, it is far larger than the intermolecular H-bonding interaction energy. The analyses of the atoms-in-molecules (AIMs), natural bond orbital (NBO) and electron density shifts show that the electron density shifts toward the trigger bond upon the intermolecular H-bond formation, leading to the strengthened trigger bond and reduced explosive sensitivity.