Table 3.
Assignment of Absorption bands and their interpretation for wood in IR wavenumber region

Wavenumber (cm-1) Interpretation Reference
3,375-3,340 O(3)H…O(5) intramolecular hydrogen bond in cellulose (Carrillo et al., 2004; Liang and Marchessault, 1959; Schwanninger et al., 2004)
3,000-2,842 C-H stretch in cellulose II (Carrillo et al., 2004; Liang and Marchessault, 1959; Oh et al., 2005; Schwanninger et al., 2004)
1,730-1,725 C=O valence vibration of acetyl- or COOH-groups (Fengal, 1993)
1,738-1,709 C=O stretch in unconjugated ketones, carbonyl and ester (Schwanninger et al., 2004)
1,685-1,655 C=O stretch (Park et al., 2017; Schwanninger et al., 2004)
1,515-1,505 Aromatic skeletal vibrations in lignin (Faix, 1991)
1,435 C-O-H bending (Schwanninger et al., 2004)
1,430-1,416 CH2 scissoring at C(6) in cellulose II (Carrillo et al., 2004; Liang and Marchessault, 1959; Nelson and O’Connor, 1964; Oh et al., 2005; Schwanninger et al., 2004)
1,364 Symmetric C-H bending (Liang and Marchessault, 1959; Schwanninger et al., 2004)
1,338-1,335 O-H in-plain deformation (Carrillo et al., 2004; Nelson and O’Connor, 1964; Schwanninger et al., 2004)
1,325-1,300 Phenolic OH in lignin (Faix, 1991)
905-892 C(1)-O-C(4) valence vibration of β-glycosidic link (Carrillo et al., 2004; Colom and Carrillo, 2002; Liang and Marchessault, 1959; Nelson and O’Connor, 1964; Schwanninger et al., 2004)