What absorbs at 3302 cm⁻¹ in an FTIR spectrum?
A band near 3302 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 5 cited sources
Possible functional-group assignments
| Functional group | Supporting facts | Cited sources | Top confidence |
|---|---|---|---|
| Hydroxyl (O-H) | 3 | 3 | 0.9 |
| N h | 2 | 2 | 0.9 |
| Amide | 1 | 1 | 0.9 |
Ranking reflects accumulated literature evidence, not a single authoritative rule. Always confirm against your sample context.
Literature behind these assignments
-
N h confidence 0.9
“Amide peak at 3302 cm-1 corresponding to -NH bond stretching.”
Salehi-Mobarakeh 等 - 2013 - Polyamide grafting onto ethylene-vinyl alcohol cop DOI: 10.1515/polyeng-2013-0104 -
Hydroxyl (O-H) confidence 0.9
“Broad band centered at 3302 cm-1 corresponds to sugar residue ν-OH groups stretching vibration (-H bonded).”
Banerjee 等 - 2022 - Optimization and Characterization of a Novel Exopo DOI: 10.3390/biom12060834 -
Amide confidence 0.9
“Explicit assignment: amide A due to NH stretching (3302 cm-1)”
Ooi 等 - 2020 - Physicochemical Characterization of Bilayer Hybrid DOI: 10.3390/ma13194352 -
Hydroxyl (O-H) confidence 0.9
“Refers to O-H axial stretching.”
Silva 等 - 2022 - Development of a Polymeric Membrane Impregnated wi DOI: 10.3390/molecules27206959 -
Hydroxyl (O-H) confidence 0.9
“Explicit assignment: 'A broad peak at 3302 was attributed to the O-H'”
Tang 等 - 2019 - Study on Preparation and Separation and Adsorption DOI: 10.3390/polym11111737
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