  Path-integral ab initio molecular dynamics (PI-AIMD) calculations have been
employed to probe the nature of chloride ion solvation in aqueous solution.
Nuclear quantum effects (NQEs) are shown to weaken hydrogen bonding between the
chloride anion and the solvation shell of water molecules. As a consequence,
the disruptive effect of the anion on the solvent water structure is
significantly reduced compared to what is found in the absence of NQEs. The
chloride hydration structure obtained from PI-AIMD agrees well with information
extracted from neutron scattering data. Inparticular, the observed satellite
peak in the hydrogen-chloride-hydrogen triple angular distribution serves as a
clear signature of NQEs. The present results suggest that NQEs are likely to
play acrucial role in determining the structure of saline solutions.
