High pressure structural and vibrational properties of nitrogen-rich compound 1,5-Diamino-1H-1,2,3,4-tetrazole

1,5-Diamino-1H-1,2,3,4-tetrazole (DAT) has attracted much attention due to its good thermal stability and high nitrogen content, as well as being a building block for a wide range of high energy density materials (HEDMs). Herein, the static compression behavior of DAT was investigated in the pressure range of 0–20 GPa using dispersion corrected density functional theory (DFT-D) calculations. The calculated crystal parameters, molecular geometry, and fundamental vibrational modes are in good agreement with those obtained experimentally at ambient condition. Furthermore, the compressibility of the unit cell constants presents an isotropic behavior. The subtle abrupt changes are observed in the lattice angle, bond lengths, dihedral angles and vibrational modes at 7 and 17 GPa, suggesting the isostructural phase transitions occurred. The Hirshfeld surfaces analysis and vibrational results suggest that the strengthening of intermolecular interactions has intensified crystal packing.