Local relaxed surface, definition

Results of vacancy energies, Edifferent oxygen surface sites 0(1-3) with and without surface relaxation, for definitions see text. The data are obtained from DFT calculations on the M015O56H22 cluster representing a local section of the MoOsfOlO) surface. All energies are given in eV. 

An a priori analysis on the reactivity and peculiarities of chemical behavior of molecules is a rather difficult but quite solvable task of theoretical chemistry. If molecules interact with a sohd surface, the complexity of its solution increases repeatedly. This is cause by the circumstances as follows firstly, an interaction occurs between two systems of different nature — molecule and surface that can be considered to be endless at the scale of partner secondly, it is difficult to simulate a surface adequately that is a macrodefect of the crystal periodic structure. Moreover, a definite grade of amorphization of surface layer is a characteristic of even typical crystal [125]. Taking into account probable relaxation and reconstruction of real surface as compared with ideal one, obtaining valid structural information on surface and subsurface layer of solids seems to be rather problematic. A cluster model of solid and its surface that is natural for chemists operating terms of local chemical bonds (despite that it is not quite suitable for the systems with covalent bond) may be considered to be fit for the objects with ionic bonds that are objects of our investigation. 

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