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Novel High-Nitrogen Content Energetic Compounds with High Detonation and Combustion Performance for use in Plastic Bonded Explosives (PBXs) and Composite Solid Propellants

Keshavarz M. H., Abadi Y. H., Esmaeilpour K., Damiri S., Oftadeh M.

Central European Journal of Energetic Materials

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2018

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Vol. 15, no. 2

364--375

EN

Five novel high-nitrogen content (N>50%) derivatives of tetrazole are introduced in the study reported here. The assessment of various properties of these compounds were performed, which include physicothermal properties (crystal density, condensed phase heat of formation, melting point, enthalpy of fusion and entropy of fusion), detonation performance (velocity and pressure of detonation, detonation temperature and power), sensitivity with respect to external stimuli (impact, shock, friction and electric spark) and combustion performance (specific impulse). The predicted results of these compounds are compared with dihydroxylammonium 5,5’-bistetrazole-1,1’-diolate (TKX-50) and octanitro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) as a high performance ionic salt and a neutral explosive, respectively. The novel energetic compounds were found to have higher detonation and combustion performance than either TKX-50 or HMX. The new explosives are therefore good candidates to obtain high detonation and combustion performance in plastic bonded explosives (PBXs) and composite solid propellants, respectively.

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Prediction of the Condensed Phase Enthalpy of Formation of Nitroaromatic Compounds Using the Estimated Gas Phase Enthalpies of Formation by the PM3 and B3LYP Methods

Oftadeh M., Keshavarz M. H., Khodadadi R.

Central European Journal of Energetic Materials

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2014

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Vol. 11, no. 1

143--156

EN

A new method is introduced to correlate the condensed phase enthalpies of formation of nitroaromatic compounds with their gas phase enthalpies of formation on the basis of the B3LYP/6-31G* and PM3 methods. For the B3LYP method, the condensed phase enthalpy of formation depends on the number of certain elements, nitro groups and aromatic rings. For the PM3 method the number of N=N or N≡N groups, and the presence or absence of three interconnected rings, in addition to some of the parameters mentioned above, are necessary in order to obtain a reliable correlation. For 72 nitroaromatic compounds, the calculated root mean square (rms) deviations of the condensed phase enthalpies of formation of nitroaromatic compounds using the B3LYP and PM3 methods are 63.63 and 32.17 kJ/mol, respectively. The results predicted on the basis of the PM3 method are compared with the best available experimental data.

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Intermolecular Interactions between TNAZ and H2O: a DFT Study

Oftadeh M., Selahvarzi S., Keshavarz M. H.

Central European Journal of Energetic Materials

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2013

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Vol. 10, no. 2

289--300

EN

All of the possible TNAZ/H2O complexes (1, 2 and 3), as well as the uncomplexed form, were fully optimized with the density functional method. Complex 3 was the most stable, with the largest corrected intermolecular interaction energy. Charge redistribution mainly occurs on the adjacent N–O...H atoms of the submolecules. Strong hydrogen bonds predominantly contribute to the interaction energies. It is energetically and thermodynamically unfavourable for TNAZ to bind with H2O and to form any stable complexes at room temperature.