Triazolo-triazine derivatives outperforming CL-20: computational discovery and substituent engineering for superior energetic materials

Abstract

Context

Triazolo[4,5-d]triazine fused-ring energetic materials exhibit excellent thermal stability and low mechanical sensitivity, but their detonation performance is generally inferior to CL-20. To overcome this limitation, this study utilizes the nitrogen-rich triazolo[4,5-d]triazine fused-ring system as a parent scaffold. By incorporating energetic functional groups—including azido, trinitromethyl, hydrazino, nitro, nitramino, cyano, nitrate ester, and dinitromethyl moieties—we designed 64 novel energetic derivatives across four distinct series (A–D). Furthermore, we systematically investigated the substituent effects on molecular energy, crystal packing, detonation performance, impact sensitivity, and electronic structure, aiming to screen for high-performance energetic candidates. Of the 64 derivatives designed, compounds D6, B8, B6, and D14 demonstrate superior performance with detonation velocities over 9.5 km/s and detonation pressures exceeding 43 GPa, surpassing RDX and HMX and nearing the performance of the benchmark explosive CL-20. D6 (D = 9.68 km/s, P = 43.82 GPa) stands out with superior detonation performance, whereas B6 exhibits the greatest crystal density at 2.0021 g·cm⁻³. These four candidates warrant priority for future experimental synthesis and evaluation.

Methods

Quantum chemical, crystal prediction, and detonation simulations were carried out at the M06-2X/6-311G(d,p) level using Gaussian 16, Materials Studio, and Multiwfn.