Table 2.
General band assignments of near-IR spectrum of plants based on the literature.
| Wavenumber (cm−1) | Wavelengths (nm) | Definition of the Spectral Assignments |
|---|---|---|
| 8403 | 1190 | C–H str. first overtone: carbohydrates |
| 8251 | 1212 | C–H str. second overtone: carbohydrates |
| 7375 | 1356 | 2 C–H str. + C–H def.: carbohydrates |
| 7168 | 1395 | 2 C–H str. + C–H def.: carbohydrates |
| 6983 | 1432 | N–H str. second overtone: proteins |
| 6748 | 1482 | O–H str. first overtone: carbohydrates |
| 6662 | 1501 | N–H str. first overtone: carbohydrates |
| 6494 | 1540 | O–H str. first overtone (intermol. H-bond): starch |
| 6394 | 1564 | N–H str. first overtone: proteins |
| 6196 | 1614 | C–H str. first overtone: carbohydrates |
| 6053 | 1652 | C–H str. first overtone: carbohydrates |
| 5896 | 1696 | C–H str. first overtone: carbohydrates |
| 5627 | 1777 | C–H str. first overtone: plant fiber composed of cellulose, lignin and other carbohydrates |
| 5507 | 1816 | O–H str. + 2 C–O str.: plant fiber composed of cellulose, lignin and other carbohydrates |
| 5120 | 1953 | C–O str. second overtone: carbohydrates |
| 4878 | 2050 | N–H sym. str. + amide II: proteins |
| 4824 | 2073 | O–H str. + O–H def.: alcohols |
| 4643 | 2154 | Amide I + amide III: proteins |
| 4439 | 2253 | O–H str. + O–H def.: starch |
| 4363 | 2292 | N–H str. + CO str.: proteins |
str.: stretching, def.: deformation.