Phase transition and chemical decomposition of liquid carbon dioxide and nitrogen mixture under extreme conditions

© 2016 Chinese Physical Society and IOP Publishing Ltd. Thermodynamic and chemical properties of liquid carbon dioxide and nitrogen (CO 2 -N 2 ) mixture under the conditions of extremely high densities and temperatures are studied by using quantum molecular dynamic (QMD) simulations based on density functional theory including dispersion corrections (DFT-D). We present equilibrium properties of liquid mixture for 112 separate density and temperature points, by selecting densities ranging from ρ = 1.80 g/cm 3 to 3.40 g/cm 3 and temperatures from T = 500 K to 8000 K. In the range of our study, the liquid CO 2 -N 2 mixture undergoes a continuous transition from molecular to atomic fluid state and liquid polymerization inferred from pair correlation functions (PCFs) and the distribution of various molecular components. The insulator-metal transition is demonstrated by means of the electronic density of states (DOS).