Molecular dynamics simulations of fine structure in oxygenK-edge x-ray emission spectra of liquid water and ice

X-ray emission (XE) spectroscopy has recently been taken as evidence for specific molecular structures in hydrogen bonded liquids. Experimentally derived and contradicting interpretations of the fine structure in the XE spectra of liquid water have been proposed in the literature. Here it is shown that all features of the XE spectra of liquid water can be explained based on ab initio molecular dynamics simulations by including core-hole excited-state dynamics. Future experiments are proposed which could discriminate between existing interpretations without relying on theory.