Some Isomers of DNNC and Radicals from Them - A DFT Treatment

Abstract

In the present density functional study, some isomers of 1,3,5,5-tetranitrohexahydropyrimidine (DNNC) have been considered within the constraints of the theory and the basis set employed (UB3LYP/6-31++G(d,p)). Various geometrical, QASR and quantum chemical properties are harvested and discussed. All the considered isomers of DNNC have exothermic heat of formation and favorable Gibbs free energy of formation values at the standard states and they are stable electronically. Based on the interfrontier molecular orbital energy gap values DNNC is found to be more sensitive to impulse stimulus than the others. Also radicals obtained from DNNC isomers considered (by the homolytic rapture of C-NO2 or N-NO2 bonds) have been focus of present interest. The radicals obtained by the cleavage of geminal C-NO2 bonds have exothermic Hº and favorable Gº values at the standard states and electronically stable as their respective parent compounds. Although, some of the radicals generated by the homolytic cleavage of N-NO2 bonds are thermo chemically exothermic and stable, like the radicals mentioned above, the radicals from the isomer having all the nitro groups in vicinal configuration decomposes by eliminating one of the geminal nitro groups.