What absorbs at 3184 cm⁻¹ in an FTIR spectrum?
A band near 3184 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 3 cited sources
Quick answer
A band near 3184 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 |
|---|---|---|---|
| Carboxyl (COOH) | 2 | 2 | 1.0 |
| Hydroxyl (O-H) | 1 | 1 | 1.0 |
| Hydrogen bond | 1 | 1 | 1.0 |
| N h | 1 | 1 | 1.0 |
| Methacrylate | 1 | 1 | 1.0 |
| Ketone | 1 | 1 | 1.0 |
| Ester | 1 | 1 | 1.0 |
| Carbonyl (C=O) | 1 | 1 | 1.0 |
| Amide | 1 | 1 | 1.0 |
| Acetate | 1 | 1 | 1.0 |
Ranking reflects accumulated literature evidence, not a single authoritative rule. Always confirm against your sample context.
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 3184 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
-
Acetate confidence 1.0
“cm-1, and 3184 C=O stretching of carboxylic acid Figure 4 shows SEM images of AC, INA and cm-1, cm-1, at 1658 NH stretching at 1623 C-N 2 ACINA.”
Wicaksono 等 - 2017 - Enhancement of solubility and dissolution rate of DOI: 10.4314/tjpr.v16i7.6 -
confidence 1.0
“The attenuated total reflectance (ATR)-FTIR spectrum showed characteristic peaks of the immobilized Cal-B on cm-1 cm-1 the matrix at peak 3184.03 (-N-H bonds) and 1683.49 (-CH deformation bonds).”
The synthesis of sulfonated polyethersulfone (SPES) and the preparation of its membranes as matrix in the immobilization of Candida antarctica lipase B (Cal-B) DOI: 10.1007/s00289-019-02932-7 -
Hydroxyl (O-H) confidence 1.0
“LLM confirmed rule peak-group candidate”
Synthesis of glutamine-based green emitting carbon quantum dots as a fluorescent nanoprobe for the determination of iron (Fe3+) in Solanum tuberrosum (potato) DOI: 10.1016/j.heliyon.2023.e15904
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 confidence-rated evidence chain — in seconds.