What absorbs at 1291 cm⁻¹ in an FTIR spectrum?
A band near 1291 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
Réponse rapide
A band near 1291 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 |
|---|---|---|---|
| Methoxy (OCH3) | 5 | 5 | 1,0 |
| Methacrylate | 5 | 5 | 1,0 |
| C-O single bond | 5 | 5 | 1,0 |
| Acetate | 5 | 5 | 1,0 |
| Amide | 4 | 3 | 1,0 |
| Hydroxyl (O-H) | 2 | 2 | 1,0 |
| Secondary amine | 2 | 2 | 1,0 |
| C n single bond | 2 | 2 | 1,0 |
| Silicon-oxygen (Si-O) | 1 | 1 | 1,0 |
| Alkene (C=C) | 1 | 1 | 1,0 |
| Carboxyl (COOH) | 1 | 1 | 1,0 |
| Fluorine (C-F) | 1 | 1 | 1,0 |
| Alkyl C-H | 1 | 1 | 0,9 |
Le classement reflète les preuves bibliographiques accumulées, et non une règle faisant autorité. Confirmez toujours dans le contexte de votre échantillon.
Matériaux possibles
| Matériel | Pics de support | Groupes chevauchants | Sources citées |
|---|---|---|---|
| PVP | 1291, 2983, 1648 | Methacrylate, Acetate | 1 |
| polyaniline | 1291, 1565, 1570 | Methacrylate, Acetate | 1 |
| copolymer | 1291, 2921, 1540 | Methacrylate, Acetate | 1 |
| PVDF | 1291, 1160, 840 | Methacrylate, Acetate | 1 |
| Fe2O3 | 1291, 1130, 1631 | Methacrylate, Acetate | 1 |
Les matériaux sont affichés uniquement lorsque le même ensemble de littérature soutient cette bande et au moins un pic caractéristique supplémentaire.
Logique du spectre
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 1291 cm⁻¹ is usually not enough for material identification by itself.
Utilisation réelle
Ce type de requête est courant dans l＇identification des polymères, le criblage des plastiques inconnus, le dépannage du contrôle qualité, la vérification des matériaux recyclés et l＇examen de l＇attribution des pics appuyée par la littérature.
Erreurs courantes
- Traiter une bande isolée comme preuve d＇un matériau sans vérifier au moins un ou deux pics de support.
- Ignorer le chevauchement : plusieurs groupes fonctionnels peuvent contribuer près du même nombre d＇onde.
- Sauter la validation lorsque des additifs, des mélanges, l＇oxydation ou la contamination peuvent déformer le spectre.
Conseil de vérification
Lorsque l＇ambiguïté persiste, validez l＇hypothèse avec DSC, GC-MS ou TGA, en particulier pour les mélanges, les échantillons dégradés et les polymères chargés.
Bibliographie derrière ces attributions
-
Acetate confiance 1,0
“Additional bands corresponding to C-O-H bending appeared at 1291 cm-1.”
Can 等 - 2023 - Choline Chloride-Based Deep Eutectic Solvent-Treat DOI: 10.3390/f14030569 -
Amide confiance 1,0
“Peak at 1291 which also confirms the self-doped structure of the copolycm-1 indicate C N stretching and C H and at 3214 mer as proposed in reaction 1.”
Dey Sadhu 等 - 2020 - Preparation and characterization of polyanilinea DOI: 10.1002/pc.25738 -
Amide confiance 1,0
“The peak at 1291 was due to C-N stretching vibration and this confirmed the presence of the amine group in pure in the memcm-1 brane matrix.”
Experimental and DFT studies on the structural and optical properties of chitosan/polyvinyl pyrrolidone/ZnS nanocomposites DOI: 10.1007/s00289-023-04700-0 -
Acetate confiance 1,0
“In addition, a of thermogram which had two melting shifting of the C-O vibration of BA at 1291.40 points at 157.0 and 188.8 °C, respectively, cm-1 to 1379.16 was proof of deprotonation in corresponding to the DES and SA melting”
Ainurofiq 等 - 2018 - Synthesis, characterization, and stability study o DOI: 10.1080/10837450 -
Acetate confiance 1,0
“In BA, the neutral carboxylic group (-COOH) had a strong carbonyl (C=O) with stretching at a peak of 1686.82 cm-1 and a weak carbonyl (C-O) stretching at 1291.40 cm-1.”
A Novel Desloratadine-Benzoic Acid Co-Amorphous Solid: Preparation, Characterization, and Stability Evaluation DOI: 10.3390/pharmaceutics10030085 -
Fluorine (C-F) confiance 1,0
“O nline 1300 1300 CF symmetric stretching and rocking 1291 [19] α PVDF 2 L ibrary”
Chipara 等 - 2020 - Spectroscopic investigations on PVDF-Fe2O3 nanocom DOI: 10.1002/app.48907 -
Acetate confiance 1,0
“The peaks at 1585-1500 cm-1 resulted from the C=C stretching vibrations of the aromatic ring cm-1 C=C at 1585-1500 resulted from the stretching vibrations of the aromatic ring while the peak at while the peak at 1291 cm-1 can be assigned to”
Kowalczuk - 2020 - FTIR Characterization of the Development of Antimi DOI: 10.3390/coatings10090818 -
Alkene (C=C) confiance 1,0
“The porphyrin peaks at 1494 cm-1 and 1291 cm-1 due to their C=C and C-N stretching can also be seen in the GO@AuNRs-TMePyP spectrum.”
Graphene Oxide-Gold Nanorods Nanocomposite-Porphyrin Conjugate as Promising Tool for Cancer Phototherapy Performance DOI: 10.3390/ph14121295
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