Computational studies on energetic performance of polynitro-substituted uric acid derivatives

To search for potential energetic materials with large energy density and acceptable thermodynamics and kinetics stability, fifteen nitro uric acid derivatives were investigated by density functional theory. The detonation properties of all the molecules were evaluated according to Kamlet-Jacobs equations and specific impulses. Calculated results show that there are good linear relationships between detonation heat, densities, detonation velocities, detonation pressures and the numbers of nitro groups, respectively. It is found that tri-nitro and tetra-nitro uric acid derivatives show detonation velocity of about 8.0 km/s, and a detonation pressure of 30 GPa, and most of the investigated molecules have higher specific impulse than hexahydro-1,3,5-trinitro-s-triazine (RDX). By analyzing bond dissociation energies (BDEs) of N-NO₂ bonds, impact sensitivity, and the free space per molecule in the unit cell, most of the investigated molecules exhibit satisfactory stability (BDEs>80 kJ/mol). The results of this study may provide basic information for the further study of this kind of compounds and the molecular design of novel energetic materials.