Periodic density functional theory study of the high-pressure behavior of energetic crystalline 1,4-dinitrofurazano[3, 4-b]piperazine

A detailed study of the structural, electronic, and optical absorption properties of crystalline 1,4-dinitrofurazano[3,4-b]piperazine (DNFP) under hydrostatic pressures of 0-100 GPa was performed using periodic density functional theory. As the pressure increases, the lattice constants and cell volumes calculated by LDA gradually approach those obtained by GGA-PW91. It was found that the structure of DNFP is much stiffer in the b direction than along the a and c axes, indicating that the compressibility of the crystal is anisotropic. As the pressure increases, the band gap gradually decreases, and this decrease is more pronounced in the low-pressure range than in the high-pressure region. An analysis of the density of states showed that the electronic delocalization in DNFP gradually increases under the influence of pressure. DNFP exhibits relatively high optical activity at high pressure. As the pressure increases, the bands in the fundamental absorption region of the absorption spectrum of DNFP become more numerous and intense.