First-principle calculations of electronic, vibrational, and thermodynamic properties of 1,3-diamino-2,4,6-trinitrobenzene.

Energy-containing materials have aroused people's widespread concern because of its admirable performance in recent years. In this paper, the electronic structure, vibrational, and thermodynamic properties of 1,3-diamino-2,4,6-trinitrobenzene (DATB) are systematically investigated by adopting the first-principle calculations. We find that lattice parameters are in excellent agreement with the previous calculated and experimental values. The vibration spectra are described in detail and the peaks in the Raman and infrared spectra are assigned to different vibration modes. Phonon dispersion curves indicate that the DATB is dynamically stable. According to the vibrational properties, the thermodynamic functions such as enthalpy (H), constant volume heat capacity (C), Helmholtz free energy (F), Debye temperature (Θ), and entropy (S) are analyzed. No corresponding experimental values have been found so far, and therefore, knowledge of these properties will provide a reference and guidance for the follow-up research.