Table 12.
Characteristic peaks before and after immersion in1M HCl in presence of the PdC-OH derivative for 24 h on the carbon steel surface at 25 °C.
| Function group | Characteristic absorption (s) cm−1 | |
|---|---|---|
| (PdC-OH) | ||
| Before | After | |
| Stretching (NH–) | (3427, 3314) | (3324, 3314) |
| Stretching (NH–) | 3055 | 3050 |
| Stretching (C–H) sp2 | – | – |
| Stretching (C–H) sp3 | 3246 | 3246 |
| stretching –OH | 2218 | 2218 |
| Nitrile (C≡N) | 1666 | 1666 |
| Stretching (–C=O) | 1606 | 1606 |
| Bending (–NH–) | 1515 | 1514 |
| Stretching (–C=C) aromatic | 1359 | 1349 |
| (C–O) Phenolic | (868, 749, 666) | (838, 750, 594) |
| Aromatic bending (C–H) sp2 | (1150, 1003) | (1151, 1002) |
| Aromatic substituted | (790, 776, 730, 669) | (792, 755, 733, 659) |