Fig. 2.

(A) Spectra of the oxygen K-edge of water at different temperatures and pressures along the liquid-gas coexistence curve. The pre-, main-, and post-edge are indicated by A, B, and C, respectively. (B) Calculated spectra for similar temperatures and densities as in A, as well as a water monomer spectrum. The densities are indicated in the figure, and the color code corresponds to the color of the respective spectrum. (C) Effect of pressure on the spectra measured at T = 400 °C in comparison to the ambient-water spectrum. (D) Calculated spectra for temperatures and densities corresponding to the experiments presented in C. (E) Comparison of the integrated post-edge intensities between 537 and 544 eV of energy loss obtained from experiment (exp.) and theory (theo.). Here, “high” refers to measurements at a similar density but higher temperature than indicated in A. (F) Energy loss position of the pre-edges for the different densities determined from theory and experiment. arb., arbitrary.