Assignment | Peak cm-1 | KL | CL | AL | PL | ACL | ASL |
---|---|---|---|---|---|---|---|
O-H stretching in aromatic and aliphatic hydroxyl groups | 3,446 | 2.00 | 1.69 | 1.62 | 1.54 | 5.56 | 5.25 |
C-H vibrations in the methyl and methylene groups | 2,938 | 0.56 | 0.42 | 0.49 | 0.55 | 0.70 | 0.64 |
2,879 | 0.36 | 0.30 | 0.33 | 0.26 | 0.34 | 0.30 | |
2,845 | 0.31 | 0.22 | 0.29 | 0.30 | 0.40 | 0.36 | |
Nonconjugated carbonyl groups (C = O stretch) | 1,724 | 0.58 | 1.12 | 0.69 | 0.46 | - | - |
Aromatic skeleton vibration | 1,594 | 1.17 | 1.25 | 1.05 | 0.73 | - | - |
1,507 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | 1.00 | |
1,422 | 0.79 | 0.66 | 0.73 | 0.40 | 0.55 | 0.43 | |
C-H deformations and aromatic ring vibrations (methyl) | 1,462 | 1.01 | 0.89 | 0.95 | 0.61 | 0.54 | 0.47 |
Phenolic hydroxyl groups | 1,384 | 0.47 | 0.61 | 0.46 | 0.14 | - | - |
Syringyl ring breathing, C-O stretch | 1,329 | 0.45 | 0.54 | 0.51 | 0.01 | 0.09 | 0.02 |
Guaiacyl C-O units | 1,268 | 0.52 | - | 0.82 | 0.64 | 0.74 | 0.89 |
Aromatic methyl ether bridges | 1,225 | 0.86 | 1.13 | 0.83 | 0.38 | 1.00 | 0.90 |
1,083 | - | 1.08 | - | 0.25 | 1.08 | 1.05 | |
C-O stretch in ester group | 1,168 | - | 1.01 | - | - | 0.80 | - |
Aromatic C-H deformation in syringyl ring | 1,123 | 1.85 | 1.38 | 1.37 | 0.47 | 1.54 | 1.26 |
Aromatic C-H in plane deformation G + S | 1,032 | 1.10 | 1.46 | 0.98 | 0.64 | 1.21 | 1.33 |
Aromatic C-H out of plane C-H out of plane in position 2 and 6 of S, and in all positions of H | 830 | 0.20 | 0.37 | 0.15 | 0.07 | 0.21 | 0.15 |