7th International Conference on Matter and Radiation at Extremes (ICMRE2024)

Through a series of Raman spectroscopic experiments on dense nitrogen/oxygen mixtures with concentrations ranging from 13% O₂ to 82% O₂, we investigated the N₂/O₂ binary phase diagram from 12 GPa to 156 GPa at 300 K. We demonstrate that, subjected to compression above 12 GPa, the mixtures experience stable structural transformations over an extensive pressure range. The formation of three novel phases, distinguished by unique Raman features, is observed. Above 100 GPa, the amorphization of nitrogen takes precedence, hindering the formation of new phases. In the pressure range from 20 GPa to 80 GPa, phase transitions to ε-O₂, ε-N₂, and ξ-N₂ initiate the development of novel phases S8 and S9. We hypothesize that the phase S7 may constitute a stoichiometric compound, (N₂)₃O₂.

High pressure,novel phases,oxygen and nitrogen