Table 2. Assignment of peaks in FTIR spectra of C. spruceanum and G. crinita.

Peak	Boliana		Capirona		Assignments	References
	Apical	Basal	Apical	Basal
1	3266	3340	3281	3315	Lignin, cellulose and hemicellulose: OH intramolecular and intermolecular stretching.	[32]
2	2923	2922	2923	2923	Lignin, cellulose and hemicellulose: symmetric methyl and methylene stretching.	[32]
3	2853	2857	2854	2855	Lignin and hemicellulose: asymmetric methyl and methylene stretching.	[32]
4	1718	1733	1730	1731	Hemicellulose: C = O stretching in unconjugated ketone, carbonyl, and aliphatic groups. Extractives: C = O stretching in ester carbonyl.	[17, 33]
5	-	1622	1621	1623	Flavones and calcium oxalate: C = O stretching.	[33]
6	1603	1598	-	-	Lignin and extractives: aromatic ring vibration.	[17, 33]
7	1518	1508	1516	1511	Lignin and extractives: aromatic skeletal vibrations.	[17, 33]
8	-	-	-	1447	Cellulose, lignin, and hemicellulose: O-H in-plane bending.	[34]
9	-	1422	1417	1419	Lignin: C = O stretching and aromatic skeletal vibration. Carbohydrates: CH and OH bending.	[16–18, 32]
10	1371	1372	1373	1371	Cellulose and hemicellulose: CH bending.	[32, 35]
11	1320	1319	1318	1318	Cellulose: CH2 wagging.	[32, 35]
12	1243	1240	1244	1239	Polysaccharides: C-O stretch and O-H in plane	[36]
13	-	1155	1150	1152	Cellulose: C–O–C asymmetric stretching	[32]
14	1104	-	-	1099	Cellulose and hemicellulose: C–O–C stretching. Lignin: Aromatic C–H in-plane deformation.	[32, 35]
15	1032	1032	1024	1021	Holocellulose and lignin: C–O stretching.	[33]
16	893	897	896	897	Cellulose: C1–H deformation	[33]