Table 3: IR spectra data of the Schiff bases ligands and their metal complexes (1)–(6).
| Compound | IR data (cm−1) | ||
| ν(OH) | νν(CH⚌N)SB | ν(M─N) | |
| L1 | — | 1680 (S) | — |
| [Fe(L1)2Cl3]2H2O (1) | 3343 (W) | 1686 (S) | 415 (W) |
| [Ni(L1)2Cl2]2H2O (2) | 3344 (W) | 1686 (S) | 419 (W) |
| [Cu(L1)2Cl2] (3) | — | 1679 (S) | 417 (W) |
| L2 | — | 1673 (S) | — |
| [Fe(L2)2Cl3] (4) | — | 1679 (S) | 429 (W) |
| [Ni(L2)2Cl2] (5) | — | 1681 (S) | 419 (W) |
| [Cu(L2)2Cl2] (6) | — | 1677 (S) | 411 (W) |