Fig. 12

Plot of the value of the reversible adhesion energy of water on the surface of a large variety of samples as a function of the n²(E_F)/t ² ratio. The partial Al3p DOS, n(E_F) is reported in Fig. 3 for the very same specimens. Values of the oxide layer thickness, t, were deduced from XPS experiments as explained in “Methods”. For the sake of comparison, we also give \({\text{W}}_{{{\text{H}}_{2} {\text{O}}}}\) data, but for materials that contain no Al3p states (e.g. window glass or stainless steel) and therefore place the data at the origin of the x-axis. The inset shows the same information, but plotted as a function of the Al-concentration in the specimens. When relevant, we used the same symbol for a sample that we could obtain with different values of the oxide thickness (the higher the thickness, the larger the size of the symbol). The data align along two sets of lines, depending on whether they contain a large concentration of 3d metals (Cr, Mn, Fe, upper line) or merely Cu (lower line)