A B3LYP and MP2(full) theoretical investigation into the strength of the C-NO2 bond upon the formation of the molecule-cation interaction between Na+ and the nitro group of nitrotriazole or its methyl derivatives

Structure and electrochemical properties for complexes of nitrocompounds with inorganic ions: A theoretical approach

Reduction and oxidation (redox) reactions are widely used for removal of nitrocompounds from contaminated soil and water. Structures and redox properties for complexes of nitrocompounds, such as 2,4,6-trinitrotoluene (TNT), 2,4-dinitrotoluene (DNT), 2,4-dinitroanisole (DNAN), and 5-nitro-2,4-dihydro-3H-1,2,4-triazol-3-one (NTO), with common inorganic ions (Na(+) , Cl(-) , NO3-) were investigated at the SMD(Pauling)/PCM(Pauling)/MPWB1K/TZVP level of theory. Atoms in molecules (AIM) theory was applied to analyze the topological properties of the bond critical points involved in the interactions between the nitrocompounds and the ions. Topological analyses show that intermolecular interactions of the types O(N)…Na(+) , C-H…Cl(-) ( ONO2-), and C…Cl(-) ( ONO2-) may be discussed as noncovalent closed-shell interactions, while N-H···Cl(-) ( ONO2-) hydrogen bonds are partially covalent in nature. Complexation causes significant decrease of redox activity of the nitrocompounds. Analysis of the reduction potentials of the complexes obtained through application of the Pourbaix diagram of an iron/water system revealed that sodium complexes of NTO might be reduced by metallic iron. © 2016 Wiley Periodicals, Inc.

Volatilization interference in thermal analysis and kinetics of low-melting organic nitro compounds

DNTF is the most sensitive to heat while DNAN has the best thermal stability.

A comparative theoretical investigation into the strength of the trigger-bond in the Na⁺, Mg²⁺ and HF complexes involving the nitro group of R-NO₂ (R = -CH₃, -NH₂ and -OCH₃) or the C = C bond of (E)-O₂N-CH = CH-NO₂

A comparative theoretical investigation into the change in strength of the trigger-bond upon formation of the Na(+), Mg(2+) and HF complexes involving the nitro group of RNO₂ (R = -CH₃, -NH₂, -OCH₃) or the C = C bond of (E)-O₂N-CH = CH-NO₂ was carried out using the B3LYP and MP2(full) methods with the 6-311++G**, 6-311++G(2df,2p) and aug-cc-pVTZ basis sets. Except for the Mg(2+)⋯π system with (E)-O2N-CH = CH-NO₂ (i.e., C₂H₂N₂O₄⋯Mg(2+)), the strength of the trigger-bond X-NO₂ (X = C, N or O) was enhanced upon complex formation. Furthermore, the increment of bond dissociation energy of the X-NO₂ bond in the Na(+) complex was far greater than that in the corresponding HF system. Thus, the explosive sensitivity in the former might be lower than that in the latter. For C₂H₂N₂O₄⋯Mg(2+), the explosive sensitivity might also be reduced. Therefore, it is possible that introducing cations into the structure of explosives might be more efficacious at reducing explosive sensitivity than the formation of an intermolecular hydrogen-bonded complex. AIM, NBO and electron density shifts analyses showed that the electron density shifted toward the X-NO₂ bond upon complex formation, leading to a strengthened X-NO₂ bond and possibly reduced explosive sensitivity.