The three investigated OL systems follow the trends and ∆E OH prediction scheme equally well as the pure metal surfaces as shown in Figure , which indicates that the general correlations hold for mixed metal systems. The only deviation between OL and the pure metal systems we observe is in the correlation between the AIMD predicted ∆φ AIMD and n H 2 O for the Ag monolayer systems (see Figure ). This deviation may be related to the observation that φ AIMD appears similar to that of the pure Ag system, despite the higher work function of the overlayer systems in vacuum (see SI Table ). However, we note that the values for ∆φ AIMD could still lie within the error margins of φ AIMD (see Figure ) and future studies considering other OL systems are needed to make definitive conclusions in this regard.