Poly NEXAFS spectrum

Spectrum interpretation is best illustrated with an example. In Figure 4.2.2, the carbon K-edge NEXAFS spectrum for poly(3-hexylthiophene) (P3HT) is shown. There are four distinct peaks. The lowest energy peak, near 286 eV, is the Is n peak associated with the carbon-carbon double bonds of thiophene [30] (for P3HT, they are delocalized over the backbone). The second resonance at 288 eV is a combination of carbon-hydrogen, carbon-sulfur, and Rydberg excitations [30]. The... 

FIGURE 4.2.2 NEXAFS spectrum of poly(3-hexylthiophene) (P3HT) with labeled resonances. PEY standard experimental uncertainty is <2%. 

Figure 3. C NEXAFS spectrum of polymers. PS polystyrene, PaMS Poly (a-methyl styrene), PDMPO poly(dimethyl p-phenylene oxide). The peaks 1 through 8 correspond to the C Is transitions into orbitals of C=C n (peak 1), bC=C (peak 2), C-H a (peak 3), C=C n (peak 4), ionization threshold (peak 5), C-C a (peak 6), bC-C a and C-O a (peak 7), and C=C a (peak 8). [Reprinted with permission of Elsevier Science from Kikuma and Tonner (1996)]...

Figure6.2 NEXAFS spectrum of poly(styrene-co-acrylonitrile). Left Energy schemes related to the electronic transitions C Is— rtc=c (A) and C Is— n< N (B). Adapted with permission from Ref [9] 2002, World Scientific Publishing.

Mg.l. Electronic schematic for the nexafs photoabsorption spectrum of poly(styrene-r-acrylonitrile). The C Is binding energies were obtained from xps. Orbital energies of the C Is LUMO(jt ) transition of the phenyl (A) and acrylonitrile (B) functional groups were obtained from ah initio calculations. Reproduced from Ref. 1. 

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