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Transition metal carbides (TMC) are mostly known for their outstanding wear resistance and for their chemical stability in hostile environment which makes them perfectly fit to reactors. Structural data and surface composition have been derived for quite a number of surfaces with (100) or (111) orientation : NbC, , TiC ZrC , HfC and TaC, VC. While these surfaces generally exhibit flat, unreconstructed surfaces, the (110) surfaces of TMC's tend to reconstruct with a missing row structure. This is observed for TiC(110) TaC and, probably, on NbC(110). These phases offer ridge-and-valley structured surfaces providing nice opportunities to grow metallic nanowires along the grooves for magnetic and/or catalytic applications. They may as well be considered as templates for self-organised molecular films
Nevertheless, in spite of the many pieces of information drawn from these previous studies the knowledge is only partial regarding this type of compounds and particularly for VC0.8(110) .
Low energy electron diffraction (LEED), grazing incidence X-ray diffraction (GIXRD) and photoemission were used to decipher the detailed structural arrangement and chemical composition of the latter surface, VC0.8(110) , for different - T driven - surface vacancy concentrations. In agreement with a previous STM study, we find that the surface reconstructs with a ridge-and-valley grating structure along the [1-10] directions resulting from {001} faceting for the (3x1) and the (4x1) phases. Contrarily to the (100) face that is highly C depleted, the (110) one terminates on the vacuum side with a nearly stoechiometric VC region due to C segregation.
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