Structural and electronic properties of NaCl dissolved in water

We carried out \emph{ab initio} molecular dynamics simulations of a 1 M NaCl aqueous solution with the \emph{Qbox} code, using the hybrid functional PBE0 and the bisection technique introduced in Ref.~[1] to compute the Hartree--Fock exchange. We performed both NVT and NVE simulations. We found that the position of the Cl$^-$ and Na$^+$ energy levels is considerably improved compared to the one obtained using the PBE functional, and that the anion highest occupied orbital [2] is unaffected by the presence of the sodium counterion. We also found that the average properties obtained in the NVE ensemble and those computed in the NVT ensemble with the Bussi--Donadio--Parrinello thermostat [3] are the same, within the statistical error bars of our simulations.\\[4pt] [1] F. Gygi and I. Duchemin, \emph{J.~Chem.\ Theory\ Comput.} \textbf{9}, 582 (2013).\\[0pt] [2] C. Zhang, T. Anh Pham, F. Gygi, and G. Galli, \emph{J.~Chem.\ Phys.} \textbf{138}, 181102 (2013).\\[0pt] [3] G. Bussi, D. Donadio, and M. Parrinello, \emph{J.~Chem.\ Phys.} \textbf{126}, 014101 (2007).