A theoretical investigation into the strength of N-NO2 bonds, ring strain and electrostatic potential upon formation of intermolecular H-bonds between HF and the nitro group in nitrogen heterocyclic rings C(n)H2(n)N-NO2 (n=2-5), RDX and HMX

作者：Wang, Bao-guo; Ren, Fu-de^*; Shi, Wen-jing

来源：Journal of Molecular Modeling, 2015, 21(11): 302.

DOI：10.1007/s00894-015-2842-7

• Intermolecular H-bond
• Ring strain
• Bond dissociation energy
• Sensitivity
• Electrostatic potential
• MP2(full)

Changes in N-NO2 bond strength, ring strain energy and electrostatic potential upon formation of intermolecular H-bonds between HF and the nitro group in nitrogen heterocyclic rings CnH2nN-NO2 (n=2-5), RDX and HMX were investigated using DFT-B3LYP and MP2(full) methods with the 6-311++G(2df, 2p) and aug-cc-pVTZ basis sets. Analysis of electron density shifts was also carried out. The results indicate that H-bonding energy correlates well with the increment of ring strain energy. Upon complex formation, the strength of the N-NO2 trigger-bond is enhanced, suggesting reduced sensitivity, while judged by the increased ring strain energy, sensitivity is increased. However, some features of the molecular surface electrostatic potential, such as a local maximum above the N-NO2 bond and ring, sigma(2)(+) and electrostatic balance parameter nu, remain essentially unchanged upon complex formation, and only a small change in the impact sensitivity h(50) is suggested. It is not sufficient to determine sensitivity solely on the basis of trigger bond or ring strain; as a global feature of a molecule, the molecular surface electrostatic potential is available to help judge the change of sensitivity in H-bonded complexes.

• 出版日期2015-11
• 单位中北大学; 山西医科大学