What absorbs at 2177 cm⁻¹ in an FTIR spectrum?
A band near 2177 cm⁻¹ can point to several functional groups. Below are the most likely assignments, ranked by how much published evidence supports each — every one traceable to literature (DOI) and cross-validated against our 130,000+ reference spectra and knowledge graph.
Backed by 1 cited source
Possible functional-group assignments
| Functional group | Supporting facts | Cited sources | Top confidence |
|---|---|---|---|
| Alkyl C-H | 1 | 1 | 1.0 |
| Hydroxyl (O-H) | 1 | 1 | 1.0 |
| Carboxyl (COOH) | 1 | 1 | 1.0 |
| Aromatic ring | 1 | 1 | 1.0 |
| N-O bond | 1 | 1 | 1.0 |
| Carbonyl (C=O) | 1 | 1 | 1.0 |
Ranking reflects accumulated literature evidence, not a single authoritative rule. Always confirm against your sample context.
Literature behind these assignments
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Carbonyl (C=O) confidence 1.0
“Peaks ranging from 1670 to cm-1 addition, the peaks at 1971 cm-1, 2177 cm-1, and 2941 cm-1 are similar to the ones observed for the 1780 could be attributed to the stretching vibration of carbonyl (C=O) group of the CNTs [15].”
Performance of Carbon Nanotube/Polysulfone (CNT/Psf) Composite Membranes during Oil–Water Mixture Separation: Effect of CNT Dispersion Method DOI: 10.3390/membranes7010014
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