XAS and XES studies of carbonate and bicarbonate ions in aqueous solutions

We perform theoretical calculations to reproduce the site-selective X-ray emission spectroscopy (XES) spectrum for carbonate and bicarbonate ions in aqueous solution at the oxygen K-edge. We perform structure sampling, and using an ab initio molecular dynamics simulation, we reproduce the solute-solvent model. Relative XES peak intensities with core-hole excited state molecular dynamics simulations are calculated using density functional theory. A comparison of several models shows that a cluster model with surrounding water can describe the experimental XES spectra, and these calculations provide electronic and molecular structure information in an aqueous solution.