Ab initio structure and capacitance of the metal-water double layer

For Pt(111) and Au(111) in dilute aqueous perchlorate or fluoride electrolyte at 300 K, compute from first principles the potential of zero charge, the water orientation profile and the differential capacitance $C(\phi)$ as a function of electrode potential $\phi$, including the capacitance maximum near the potential of zero charge measured on Pt(111) and the Gouy-Chapman minimum at the potential of zero charge measured on Au(111) in dilute electrolyte. An answer is a simulation at fixed electrode potential that reproduces the measured potential of zero charge within $3.3 \times 10^{-4}\ \mathrm{statvolt}$ and $C(\phi)$ within 20 percent.

Grand-canonical ab initio molecular dynamics with explicit electrolyte compared with impedance and surface X-ray and vibrational data.