What absorbs at 3310 cm⁻¹ in an FTIR spectrum?
A band near 3310 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 8 cited sources
Quick answer
A band near 3310 cm⁻¹ is usually interpreted by checking which functional groups repeatedly co-occur there in the literature, then confirming at least one or two additional peaks in the same sample. This page ranks those assignments by accumulated evidence rather than by a single fixed textbook rule.
Possible functional-group assignments
| Functional group | Supporting facts | Cited sources | Top confidence |
|---|---|---|---|
| N h | 18 | 17 | 1.0 |
| Hydroxyl (O-H) | 10 | 10 | 1.0 |
| Amide | 3 | 3 | 1.0 |
| Secondary amine | 3 | 3 | 1.0 |
| Amine primary | 3 | 3 | 1.0 |
| Hydrogen bond | 2 | 2 | 1.0 |
| Methacrylate | 1 | 1 | 1.0 |
| Ketone | 1 | 1 | 1.0 |
| Ester | 1 | 1 | 1.0 |
| Carboxyl (COOH) | 1 | 1 | 1.0 |
| Carbonyl (C=O) | 1 | 1 | 1.0 |
| Acetate | 1 | 1 | 1.0 |
| Water (H2O) | 1 | 1 | 1.0 |
| Alkyl C-H | 1 | 1 | 1.0 |
| Silicon-oxygen (Si-O) | 1 | 1 | 1.0 |
| Silicon (Si) | 1 | 1 | 1.0 |
| Protein | 1 | 1 | 1.0 |
| Metal hydroxyl | 1 | 1 | 0.9 |
Ranking reflects accumulated literature evidence, not a single fixed rule. Always confirm against your sample context.
Possible materials
| Material | Supporting peaks | Overlapping groups | Cited sources |
|---|---|---|---|
| copper oxide | 3310, 624, 1686 | Hydroxyl (O-H), Amide | 1 |
| bio-based | 3310, 1720, 1740 | Amide, Hydroxyl (O-H), N h | 1 |
| PET | 3310, 1408, 800 | Amide, N h | 1 |
Materials are shown only when the same literature pool supports this band and at least one additional characteristic peak.
Spectrum logic
This band becomes meaningful only when read with its neighboring peaks. In practice, analysts first look at the assignments above, then check whether the same sample also shows other peaks expected for the same structural motif. A lone band near 3310 cm⁻¹ is usually not enough for material identification by itself.
Real-world usage
This type of query is common in polymer identification, unknown plastic screening, QC troubleshooting, recycled-material verification, and literature-backed peak assignment review.
Common mistakes
- Treating one isolated band as proof of a material without checking at least one or two supporting peaks.
- Ignoring overlap: multiple functional groups can contribute near the same wavenumber.
- Skipping validation when additives, blends, oxidation, or contamination may distort the spectrum.
Verification advice
When ambiguity remains, validate the hypothesis with DSC, GC-MS, or TGA, especially for blends, degraded samples, and filled polymers.
Literature behind these assignments
-
confidence 1.0
“The presence of L-GSH in Ag@SG (3) nanoclusters is confirmed by several bands (Supporting N-H 3310Information Figure S2b), such as the stretching at cm-1.”
Farrag 等 - 2012 - Preparation and Spectroscopic Properties of Monola DOI: 10.1021/jp210453v -
N h confidence 1.0
“Depending on the cm-1 strength of the hydrogen bond, the NH stretching vibration from amides produces bands at 3310 cm-1 cm-1 and 3270 that are localized on the NH group [38].”
Gupta 等 - 2022 - In vitro cell composition identification of wood d DOI: 10.1098/rsos.201935 -
N h confidence 1.0
“The broad peaks 3310-3318, cm-1 and 421-424 correspond to the existence of -NH and -OH groups respectively, as well 2”
Ojo 等 - 2016 - Biomedical and Catalytic Applications of Gold and DOI: 10.1109/TNB.2016.2559161 -
confidence 1.0
“For the effect of the NCO/OH ratio, the increment of the absorbance band at the N-H hydrogen bonded (3310 cm-1) de4.”
Effects of NCO/OH Ratios on Bio-Based Polyurethane Film Properties Made from Acacia mangium Liquefied Wood DOI: 10.3390/polym15051154 -
Hydroxyl (O-H) confidence 1.0
“cm-1, nanoparticles mixture showed two broad peaks at 3310 and 1638 which correspond to O-H 8 9 10 bond of phenols and N-H bend of primary amines of proteins.”
Yugandhar 等 - 2019 - Biofabrication, characterization and evaluation of DOI: 10.1088/2053-1591/ab0db9 -
Hydroxyl (O-H) confidence 1.0
“At 2800 to 3800 cm-1, the combined O-H and N-H band of amide and amine stretching could be detected, and the band at 3310 cm-1 was caused by its hydroxyl (O-H) group [65,66].”
ALSamman 和 Sanchez - 2023 - Adsorption of Copper and Arsenic from Water Using DOI: 10.3390/polym15092192 -
Silicon (Si) confidence 1.0
“The bands observed at 3190 The less intense bands at 449, 496, 582, 678, and 725cm-1 and 3310 are attributed to Si-O stretching, the bands at are attributed to Si-O bending and some bands 3379cm-1 3381cm-1 mightbeduetoCa-Ostretchingvibratio”
Ahmad 等 - 2021 - Spectroscopic Analysis for Harnessing the Quality DOI: 10.1155/2021/6629640 -
Hydroxyl (O-H) confidence 1.0
“Out of The absorption bands at 3310 to O-H bond stretching, which appears in the case of the three isolates, VT3.12 showed the high degradation activity powder sample degraded at 12 h.”
Biological degradation of polyethylene terephthalate by rhizobacteria DOI: 10.1007/s11356-022-20324-9
Have a spectrum with this band?
Upload your FTIR spectrum and get a full interpretation report — peak assignments with literature citations, library matches, and a literature-backed analysis — in seconds.