Accounting for Auger yield energy loss for improved determination of molecular orientation using soft x-ray absorption spectroscopy
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32.In order to evaluate z we assumed that the – part of the SF–SAM molecule is oriented parallel with the sample normal. This assumption was based on earlier measurements on similar systems. However, we note that even if the – chain is slightly titled from the sample normal and thus the thickness of the layer – decreases, the error cased by our approximation is well within the acceptable range assuming the experimental uncertainty in determining the ratio. Moreover, as discussed later in the article, our choice for the orientation of the – part of the molecule is justified from the analyzed chain tilt angle.
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38.We note that the tilt and twist angles determined from NEXAFS represent average values. For example, there is no straightforward way to discriminate between the case of all chains homogeneously tilted by the same angle and the case of a disordered system with a broad distribution of tilt angles. We thus express our results on the orientation of the SF moieties in terms of the average tilt angle and an average twist angle Moreover, due to the nature of the polarization dependencies of the NEXAFS signal intensities one cannot distinguish between a completely disoriented sample and a sample, whose chains are all tilted by 54.7°, the so called, “magic angle.”
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43.Note there is an error in Eq. (22) in Ref. 16. The correct form should read However, because in our case, and the corrected Eq. (22) and the original Eq. (22) in Ref. 16 give the correct form of
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