Novel All-Nitrogen Molecular Crystals Composed of Tetragonal N₄ Molecules

A computational study promises insight into molecular crystals consisting of the tetrahedral form of N₄ molecules (Td-N₄). Here, our efforts are focused on theoretically predicting the existence of the molecular crystals consisting of Td-N₄ molecules. On the basis of the first principles of Born–Oppenheimer molecular dynamics under constant temperature and pressure, and geometry optimizations under hydrostatic pressures without any constrained parameters, molecular crystals consisting of Td-N₄ molecules were confirmed to be dynamically and thermally metastable. Our analysis shows that, with high detonation performance and high stability, these Td-N₄ molecular crystals can indeed be potential candidates as high-energy density explosives.