Molecular Design of New Nitramine Explosive: 1,3,5,7-Tetraaza-1,2,3,5, 6,7-hexahydros-indacene Derivatives

Abstract

Two new nitramine explosives, 1,3,5,7-tetraaza-1,2,3,5,6,7-hexahydros-indacene derivatives (molecules A and B) have been proposed and studied by density functional theory (DFT) and molecular mechanics (MM) methods. The geometric and electronic structures, infrared spectrum (IR) and thermodynamic properties of molecules A and B were investigated at B3LYP/6-31+G(d) level. Heats of formation (HOFs) were predicted through designed reactions. Detonation performance was evaluated by using the Kamlet–Jacobs equations based on the crystal densities and heats of formation. Results indicate that molecule A (D = 8.74 km·s⁻¹, P = 35.24 GPa) performs similarly to HMX and molecule B (D = 9.21 km·s⁻¹, P = 39.55 GPa) outperforms HMX and satisfies the energy criterion as HEDM. The stabilities of molecules A and B were investigated by HOMO, LUMO, and molecular electrostatic potential (MEP). The two new nitramine explosives having better detonation performance and stability may be superior high energetic density materials (HEDMs).

Key Words:

• density functional theory
• detonation performance
• infrared spectrum
• nitramine
• molecular electrostatic potential
• thermodynamic property

ACKNOWLEDGMENTS

This research was supported by the NSAF Foundation of National Natural Science Foundation of China and China Academy of Engineering Physics (Grant No: 11076017). We were indebted to and thank Dr. Hongchen Du (Nanjing University of Science & Technology, P. R. China) for helpful support of our work.