First-principles calculations of electronic, vibrational, and thermodynamic properties of nitrogen-rich salt of 3,6-dinitramino-1,2,4,5-tetrazine [(DAG)2(DNAT)·H2O]

In recent years, nitrogen-rich salts as green and efficient energetic materials have garnered widespread attention. This study focuses on a novel green synthesized salt, (DAG)2(DNAT)·H2O, which obtained through DNAT synthesis. Employing first-principles calculations, we conducted theoretical investigations to elucidate the electronic structure, vibrational, and thermodynamic properties of (DAG)2(DNAT)·H2O. Our computed lattice parameters align with experimental values from literature data. Analysis of the band structure and electronic states of atoms within the compound was performed. Vibrational modes for each peak in the infrared and Raman spectra were meticulously described, accompanied by phonon dispersion curves and phonon density of states plots for phonon contribution analysis. Thermochemical functions including enthalpy (H), heat capacity at constant volume (CV), Helmholtz free energy (F), Debye temperature (θ), and entropy (S) were computed based on vibrational characteristics, providing essential references for future research endeavors.