Filhol-Neurock approach

The advantages of the simple approach outlined above are the limited number of water molecules needed in the simulation and the well-defined water structure. The major drawback is that, owing to the periodicity, this water structure fits best on a (111) or (lll)-like surface, e.g., (211). There are at least two other approximations to model the water interaction. One is to include a large number of water molecules and apply molecular dynamics to determine a structure for the water and include this water arrangement in the simulations [Filhol and Neurock, 2006]. The drawbacks of this approach are the computational time required and the results sensitivity to the water structure. 

In this section, the methodology adopted by Filhol and Neurock is discussed in greater detail, particularly with respect to establishing the reference potential and determining electrochemical potential-dependent structural and energetic transformations at the metal olution interface. A more complete discussion of the approach can be found in the paper by Taylor et al. [26]. Methanol dehydrogenation over Pt(lll) is used once again as a case study to examine potential-dependent chemical reactions. 

We start om discussion with the adsorption and activation of water over Pd(lll) and then advance to other metals. Filhol and Neurock l used the approach described above to examine the potential-dependent behavior of water over Pd(lll). In the absence of an electrochemical field or potential, water adsorbs on Pd(lll) with its oxygen end directed down towards the surface and its molecular plane tilted away from the surface normal vector by approximately 60°, as shown in Fig. 6.11. 

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