Table 4.
Stepwise thermal degradation data obtained from TGA curves for the metal complexes.
| Complex | Molar mass | TG range (°C) | DTGmax (°C) | Weight loss | Predicated intermediates and final products | Metallic residue (calcd. %) found | |
|---|---|---|---|---|---|---|---|
| Calcd. | Found | ||||||
| [L2Zn]⋅H2O, C22H24N8S2O3Zn | 577.3 | 32–120 | 72 | 3.1 | 2.9 | H2O | ZnS |
| 136–328 | 261 | 49.8 | 49.2 | 2-BTA | (16.5) 17.4 | ||
| [L2Cu], C22H22N8S2O2Cu | 557.5 | 158–316 | 216 | 51.6 | 51.2 | 2-BTA | CuS |
| 449–549 | 500 | 31.2 | 30.9 | SO2 + L1 | (17.2) 17.9 | ||
| [L2Ni], C22H22N8S2O2Ni | 552.7 | 32–99 | 78 | 1.6 | 1.5 | 1/2 H2O | |
| 222–331 | 290 | 52.1 | 51.8 | 2-BTA | NiS | ||
| 414–608 | 531 | 31.4 | 31.1 | SO2 + L1 | (16.4) 17.1 | ||
| [L2Co], C22H22N8S2O2Co | 552.9 | 222–331 | 290 | 52.08 | 52.7 | 2-BTA | CoS |
| 414–608 | 531 | 31.4 | 29.9 | SO2 + L1 | (16.5) 17.4 | ||
| 222–331 | 290 | 52.08 | 52.7 | 2-BTA | CoS | ||
BTA = benzotriazole ring, L1 = C6H10N2.