Structure and properties of 1,3,5-triazine and 1,2,4-triazole linked energetic derivatives with varied energetic functional groups.

Context: A series of 49 derivatives, designed as the A series, were theoretically modeled by connecting 1,3,5-triazine and 1,2,4-triazole moieties via a direct C-N linkage. The properties of these compounds, incorporating various substituent combinations, were systematically investigated. Computational analysis revealed that nitro, nitrate ester, and nitramino groups significantly enhance the oxygen balance of the designed energetic molecules. Furthermore, the azide and cyano groups were found to contribute substantially to the heat of formation. Intramolecular interaction studies indicated that nitramino facilitates hydrogen bond formation. Screening identified compound A6-6 as exhibiting the optimal detonation characteristics, with a specific energy (Q) of 6.02 kJ/g, detonation velocity (D) of 8.64 km/s, and detonation pressure (P) of 34.24 GPa. Additionally, A6-6 exhibits a density (1.909 g/cm³) surpassing HMX and superior oxygen balance.

Method: Structural optimizations of all 49 derivatives were performed using the DFT-D3-B3LYP functional with the 6-311G**(d,p) basis set in Gaussian 16, followed by single-point energy calculations employing the M06-2X-D3/def2-TZVPP basis set. Wavefunction analysis was conducted using Multiwfn 3.8 package.