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Chapter 4 81
XANES spectra (Figure 4.18) show deviation of the edge jump derivative for the samples
1a-d from that one of the parent Ru-MOF. For 1a-c, the position of edge jump gradually
shifts to the lower energies, suggesting reduced Ru-sites with oxidation states lower than
2+ or 3+. We relate this observation to the generation of defects A in the samples 1a-c.
However, the position of the edge jump in case of the sample 1d moved again to higher
energies, illustrating that the amount of reduced Ru-species is now decreased with
respect to samples 1a-c. The different tendency suggests that defects B may also be
created when 5-OH-ip linker was incorporated into the framework at ratios higher than
32%. The same trend has been observed for the 5-NH2-ip linker (samples 3a-c). Indeed,
the XANES spectra of the samples 3a-b suggest again the presence of reduced Ru δ+
(0