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3.6 p3ht/zno interface: high deposition rate 43Figure 3.14.: Structure factor in the xy plane for the HDR 100 (left)and 010 (right) systems.For the 100 HDR system (left panel of Figure 3.14) thepeaks of backbone and π − π distance are smaller andbroader and the S xy exhibits much less structure in therange 0.3-1.1.The S xy curve of the 100 HDR case is reminescent tothe case of P3HT on glass. In fact, for crystalline polymeron glass a peaked region occurs at 1.6 Å −1 close to ourπ − π and backbone peaks and a more flat GIXD signalis found at smaller trasferred momentum. The agreementwith the 100 polymer surface supports the experimentalobservation that the polymer π channels are parallel to theglass substrate exposing the hexyl chains. In the case of thepolymer on ZnO experiments show that the crystallinitypeaks are completely lost.A direct comparison with experiment is difficult becauseof the poor control of the crystalline surface. Experimentson ZnO gives a P3HT signal that does not correspond toour calculated 100 nor 010 crystalline surfaces. We attribute