Supercritical fluid liquid-solid coexistence curve

If, however, we increase p at constant T, the supercritical fluid will change to a solid. In the phase diagram of H2O, the coexistence curve for ice VII and liquid shown in Fig. 8.4 extends to a higher temperature than the critical temperature of 647 K. Thus, supercritical water can be converted to ice VII by isothermal compression. Refs. [162] and [9]. 

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