Table 1 FTIR spectra band assignments [47–53]
No. | Wavenumber (cm−1) | Assignment |
|---|---|---|
1 | 1708–1738 | Stretching of C=O unconjugated to aromatic rings (oxidized side chains, non-conjugated carbonyl) |
2 | 1655 | Stretching of C=O conjugated to aromatic rings (conjugated carbonyl) |
3 | 1590–1609 | Aromatic ring vibrations and C=O stretching |
4 | 1500–1515 | Aromatic ring vibrations |
5 | 1455/1425 | C–H deformation and aromatic ring vibration |
6 | 1420–1424 | Aromatic ring vibrations |
7 | 1375 | C–H stretching in cellulose and hemicellulose |
8 | 1330–1325 | Syringyl nuclei (C–O stretching) |
9 | 1270-1268/1244 | Guaiacyl nuclei (C–O stretching) |
10 | 1221 | C–C, C–O, C=O stretching in G ring |
11 | 1160 | Deformation vibrations of C–H bonds on benzene rings |
12 | 1120 | Carbon ring stretching of cellulose |
13 | 1115 | Vibrations of ester linkage |
14 | 1086 | C–O stretch of secondary alcohols and aliphatic ethers |
15 | 1048 | C–O stretch in cellulose and hemicellulose |
16 | 1060/1040/1030 | C–O stretch (primary alcohols) |