Bulk water, potential energy surfaces , structural

The change in the ion hydration energy between the bulk and the water-air interface for structure-making ions is so large compared to kT, that these ions practically do not approach the interface. The change is not so steep when a solid interface is immersed in water, particularly when the surface has sites which can bound structure-making ions. In what follows, it will be assumed that the anions are structure breaking and hence interact with the surface via an attractive potential of the type (Wx >0, see Fig. 3a) ... 

It has been recognized that the structure of water near the interface determines the adsorption behavior of ions on the metal surface in specific ways [24, 30, 31]. Therefore, realistic models of the metal phase are needed in order to describe the inhomogeneity and orientational anisotropy in the aqueous phase adequately. Contrary to the situation for bulk liquid where reliable interaction potentials, from empirical parametrizations or from ab initio calculations, are available, the quantum chemical description of interactions between molecular adsorbates and metal substrates poses substantial problems due to the complexity of the system. Systematic studies contribute to the understanding of the key factors that determine the structure and dynamics at the electrochemical interface. In the present work the influence of water adsorption energy (for many transition metal surfaces a known experimental quantity [32]), surface corru-... 

A review of First Principles simulation of oxide surhices is presented, focussing on the interplay between atomic-scale structure and reactivity. Practical aspects of the First Principles method are outlined choice of functional, role of pseudopotential, size of basis, estimation of bulk and surface energies and inclusion of the chemical potential of an ambient. The suitability of various surface models is discussed in terms of planarity, polarity, lateral reconstruction and vertical thickness. These density functional calculations can aid in the interpretation of STM images, as the simulated images for the rutile (110) surface illustrate. Non-stoichiometric reconstructions of this titanium oxide surface are discussed, as well as those of ruthenium oxide, vanadium oxide, silver oxide and alumina (corundum). This demonstrates the link between structure and reactivity in vacuum versus an oxygen-rich atmosphere. This link is also evident for interaction with water, where a survey of relevant ab initio computational work on the reactivity of oxide surfaces is presented. 

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