The influence of ring strain and conjugation on the reaction energies of the NO2 fission of nitramines: A DFT study

Investigation of the thermal decomposition and stability of energetic 1,2,4-triazole derivatives using a UV laser based pulsed photoacoustic technique

The paper reports PA fingerprint spectra, thermal stability and efficiency as rocket fuel for nitro rich energetic materials labeled as p-Me-DNPT, p-OMe-DNPT and p-NH₂-DNPT using UV 266 nm based pulsed photoacoustic pyrolysis technique between 30–350 °C range.

Quantum chemical study on nitroimidazole, polynitroimidazole and their methyl derivatives

The insensitive explosive candidates, nitroimidazoles, polynitroimidazoles and their methyl derivatives, are investigated using density functional theory (DFT). The homolytic bond dissociation energies (BDEs) corresponding to -NO2 group removal from carbon or nitrogen site on imidazole ring were calculated at B3P86/6-311G** level, and the weakest bond has been determined. Further, a correlation is developed between impact sensitivity h50 and the ratio (BDE/E) of the weakest bond BDE to the total energy E, and we extrapolate this relationship to predict the impact sensitivities for compounds where experiments are not available. It is found that most of the title compounds are insensitive towards impact stimuli with their h50 larger than 60.0cm. Heats of formation (HOFs) for the 21 title compounds at 298K in gas are also determined both at B3LYP/6-311G** and B3P86/6-311G** levels using isodesmic work reactions. The calculated BDEs and HOFs consistently indicate that C-nitro-substituted imdazole is more stable than the corresponding N-substituted one, and the introduction of methyl on C increases the stability whereas the methyl attached to N atom decreases the stability.

Ab initio and DFT study on 1,4-dinitroglycoluril configurational isomers: cis-DINGU and trans-DINGU

cis-1,4-Dinitroglycoluril (1,4-dinitrotetrahydroimidazo[4,5-d]imidazole-2,5-(1H,3H)-dione, C(4)H(4)N(6)O(6), known as DINGU in the literature) is an important explosive regarded as one of the potential ingredients for LOVA (low vulnerability ammunition) applications. However, there is no study concerning trans-DINGU, to the best of our knowledge. Thus, in the present study the structural and electronic properties of the configurational isomers of DINGU (cis- and trans-isomers) have been investigated by performing density functional theory (DFT) calculations at B3LYP/6-31G(d,p), UB3LYP/6-31G(d,p) levels and also ab initio calculations at RHF/6-31G(d,p) and UHF/6-31G(d,p) levels. The optimized geometries, vibrational frequencies, electronic structures, and some thermodynamical values for the presently considered DINGU isomers have been obtained in their ground states. Comparing the calculated energy data (total electronic energy, heat of formation values and homolytic bond dissociation values of N-NO(2)) and the calculated bond lengths, cis-DINGU was found to be a more stable molecule than the trans-isomer.