Hydrogen bonds at metal surfaces: Universal scaling and quantification of substrate effects

Simple bio-molecules demonstrate a propensity to form hydrogen-bonded networks. Here, individual hydrogen-bond energies are determined through topological analysis of the theoretical electron density for a variety of systems, demonstrating the existence of a universal relationship between hydrogen-bond length and strength. Comparison of local hydrogen-bond strength to global stabilisation allows the quantification of contributions to intermolecular interactions within surface overlayers in unprecedented detail.