VO x ultrathin epitaxial films (0.8=<x=<1.3), grown on Pt(111) by evaporating vanadium in a controlled water background (1x10 - 7 Pa), have been chemically characterised by X-ray photoelectron spectroscopy (XPS) and X-ray-excited Auger electron spectroscopy (AES), which confirm the presence of V(II). The VO film shows a NaCl-type structure exposing the (111) plane, as proven by XPD. Multiple scattering calculations are compatible with an O-terminated surface and a surface relaxation of the outermost atomic layers, which leads to a V O bond length contraction amounting to 7%.