A theoretical investigation on the structures,densities, detonation properties,and pyrolysis mechanism of the nitro derivatives of phenols

The nitro derivatives of phenols are optimized to obtain their molecular geometries and electronic structures at the DFT‐B3LYP/6‐31G* level. Detonation properties are evaluated using the modified Kamlet–Jacobs equations based on the calculated densities and heats of formation. It is found that there are good linear relationships between density, detonation velocity, detonation pressure, and the number of nitro and hydroxy groups. Thermal stability and pyrolysis mechanism of the title compounds are investigated by calculating the bond dissociation energies (BDEs) at the unrestricted B3LYP/6‐31G* level. The activation energies of H‐transfer reaction is smaller than the BDEs of all bonds and this illustrates that the pyrolysis of the title compounds may be started from breaking O? H bond followed by the isomerization reaction of H transfer. Moreover, the C? NO₂ bond with the smaller bond overlap population and the smaller BDE will also overlap may be before homolysis. According to the quantitative standard of energetics and stability as a high‐energy density compound, pentanitrophenol essentially satisfies this requirement. In addition, we have discussed the effect of the nitro and hydroxy groups on the static electronic structural parameters and the kinetic parameter. © 2009 Wiley Periodicals, Inc. Int J Quantum Chem, 2010