Table 2 FTIR frequencies and functional groups for A. Al-Azhar MNE ON864448.1 EPS
Wave number (cm−1) | Vibration shape | Assignment groups |
|---|---|---|
3267.54 | Broad band | O–H |
2950.59 | Weak band | C–H |
1620 | Weak band | Asymmetric vibration belongs to (C=O) of the carboxylate ion (COO–) |
1433.45 and 1392.45 | Scissoring strong band | (–CH2) scissoring and (–OH) bending vibrations, respectively |
1220.06 | Weak band | The asymmetric stretching of the sulfate group (S=O) |
1020.07 | Medium band | C-O group of uronic acid |
856.78 | Strong sharp band | Secondary axial sulfate (C–O–S) |
559.16 | Strong band | The symmetrical vibration of the sulfate group (O–S–O) |