| Functional groups | Kind of bonding | Wavenumber (cm−1) |
| O-H/H2O | Υ | 3395, between 1610 and 1625 cm−1 [26] |
| Δ | 1536 | |
| O-H/Ni-OH | Υ | 3420 |
| CH/CH3 | υas | 2957 |
| υs | 2872 | |
| CH/CH2 | υas | 2923 |
| υs | 2853 | |
| C-C | υas | 920 |
| OCO, v(C-O + δ(O-C = O)) | υas | 1581 |
| υs | 1313 - 1320 cm−1 and 825 - 826 cm−1 [20] | |
| Δ | 674 | |
| Π | 641 | |
| (CH2)6 | Δ | 1320 |
| Ρ | 743 | |
| Ni-O | Υ | 591, 530 and 481 cm−1 were assigned to: V(O-Ni-O), V(Ni-O) + V(C-C) and V(Ni-O), respectively [17] [27] . |
| Co-O | Υ | 370 |