| Sample “in natura” | Sample after sun exposure | Organic group | Vibration mode | ||
| Wave number cm−1 | Band area cm2 | Wave number cm−1 | Band area cm2 | - | - |
| 2951, 2920, 2852 | 2426.27 | 2951, 2920, 2852 | 2319.07 | -C-H (CH3), -C-H (CH2) | Asymmetric and symmetrical axial deformation |
| 1747 | 85.42 | 1747 | 83.11 | -C=O | Axial deformation |
| 1670 | 3.11 | Absent | - | C=C (trans) | Axial deformation |
| 1652 | 10.35 | Absent | - | C=C (cis) | Axial deformation |
| 1456 | 340.99 | 1460 | 388.63 | -C-H (CH2) | Symmetrical angular deformation |
| 1417 | 2.48 | Absent | - | =C-H (cis) | Angular deformation |
| 1396 | 1.89 | Absent | - | =C-H (cis) | Angular deformation |
| 1375 | 110.29 | 1375 | 134.35 | -C-H (CH3) | Symmetrical angular deformation |
| 1230 | 6.55 | 1238 | 5.36 | C-O | Axial deformation |
| 1217 | 0.85 | Absent | - | C-O | Axial deformation |
| 1163 | 79.60 | 1159 | 72.47 | C-O | Axial deformation |
| 721 | 72.45 | 721 | 68.78 | -(CH2)n- | Asymmetric angular deformation |