What absorbs at 1191 cm⁻¹ in an FTIR spectrum?
A band near 1191 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 4 cited sources
Quick answer
A band near 1191 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.
Attributions possibles de groupes fonctionnels
| Groupe fonctionnel | Faits à l'appui | Sources citées | Confiance maximale |
|---|---|---|---|
| C c single bond | 2 | 1 | 1,0 |
| Siloxane (Si-O-Si) | 1 | 1 | 1,0 |
| Silicon-oxygen (Si-O) | 1 | 1 | 1,0 |
| S eq o | 1 | 1 | 1,0 |
| Aromatic ring | 1 | 1 | 1,0 |
| Hydroxyl (O-H) | 1 | 1 | 1,0 |
| Methoxy (OCH3) | 1 | 1 | 1,0 |
| Methacrylate | 1 | 1 | 1,0 |
| C-O single bond | 1 | 1 | 1,0 |
| Acetate | 1 | 1 | 1,0 |
Le classement reflète les preuves bibliographiques accumulées, et non une règle faisant autorité. Confirmez toujours dans le contexte de votre échantillon.
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 1191 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.
Bibliographie derrière ces attributions
-
C c single bond confiance 1,0
“C-C-Cinplanebend 102 1153.454 1114.2 23.5 CHinplanebend 163 366.7925 354.3 26.7 C-C-Cinplanebend 103 1146.305 1107.3 48.5 CNstretching 1222.3 164 357.1741 345.0 36.5 C-C-Cinplanebend 104 1137.087 1098.4 579.3 CNstretching 1191 165 352.9152”
Computational and spectral studies of 3,3'-(propane-1,3-diyl)bis(7,8-dimethoxy-1,3,4,5-tetrahydro-2H-benzo[d]azepin-2-one) DOI: 10.1016/j.heliyon.2019.e02420 -
Acetate confiance 1,0
“Specifically, the intensity of absorption at 1205 cm-1 (δC-O-H, aromatic ring) and 1191 cm-1 (νC-O, glycosidic bond) decreased in the DAU:POSS complex.”
Piorecka 等 - 2020 - Hydrophilic Polyhedral Oligomeric Silsesquioxane, DOI: 10.3390/ma13235512 -
S eq o confiance 1,0
“The cm-1 absorption peak at 1191 was assigned to the S=O asymmetric vibration peak of -SO 3H groups [46].”
Preparation of a Cation Exchange Membrane by a Sol-Gel Method-Based Polyvinyl Alcohol to Improve Alkali Recovery via Diffusion Dialysis in the Textile Industry DOI: 10.3390/separations10070370 -
confiance 0,7
“Spectral structural carbohydrates peak area”
de Oliveira 和 Yu - 2023 - Quantitation of relationship and development of nu DOI: 10.5713/ab.22.0076
Avez-vous un spectre avec cette bande ?
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