What absorbs at 3293 cm⁻¹ in an FTIR spectrum?
A band near 3293 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 3293 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 |
|---|---|---|---|
| N h | 5 | 5 | 1,0 |
| Alkyl C-H | 5 | 5 | 1,0 |
| Hydroxyl (O-H) | 5 | 5 | 1,0 |
| Amide | 2 | 2 | 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 |
| Carboxyl (COOH) | 1 | 1 | 1,0 |
| Phenolic | 1 | 1 | 0,8 |
Le classement reflète les preuves bibliographiques accumulées, et non une règle faisant autorité. Confirmez toujours dans le contexte de votre échantillon.
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 3293 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
-
Alkyl C-H confiance 1,0
“cm-1) The acetylenic C≡C bond stretching (2110 and acetylenic ≡C-H bond stretching (3293 peaks of 2-ethynylpyridine monomer were not seen in the FT-IR spectrum of polymer.”
Gal 等 - 2016 - Synthesis and Characterization of a Water-Soluble DOI: 10.12693/APhysPolA.129.642 -
Hydroxyl (O-H) confiance 1,0
“As observed, 𝜈, cm-1 a dominant broad peak centered at 3293 is due to the hydroxyl stretching vibrations.”
Power-Dependent Nonlinear Optical Behaviours of Ponceau BS Chromophore at 532 nm via Z-Scan Technique DOI: 10.1016/j.jphotochem.2020.112574 -
Alkyl C-H confiance 1,0
“- - - - O-H asymmetric and symmetric stretching 3293 3356 C-H asymmetric and symmetric stretching 2876 2872 2881 2858 2851 2851 vibration - - - - C=O stretching in aldehydes 1772 1778 - - - - - N-H bending of NH group (scissoring) 1673 2 -”
Sukprasert 等 - 2020 - Synchrotron FTIR Light Reveals Signal Changes of B DOI: 10.1155/2020/6149713 -
confiance 1,0
“sin2 1.83 N-H bend 1184 131 N-H(cid:5)(cid:5)(cid:5) stretching 3293 249 N-H stretching 3345”
Ay 和 Aydinli - 2004 - Comparative investigation of hydrogen bonding in s DOI: 10.1016/j.optmat.2003.12.004 -
Hydroxyl (O-H) confiance 1,0
“In the spectrum of pure capsaicin, the broad cm-1 cm-1 absorption peaks at 3293.43 and 2926.43 might be associated with the stretching of -OH bond and -C-H aliphatic stretching vibrations, respectively;”
Microencapsulation of Capsaicin in Chitosan Microcapsules: Characterization, Release Behavior, and Pesticidal Properties against Tribolium castaneum (Herbst) DOI: 10.3390/insects14010027 -
confiance 1,0
“Peaks observed at 3293 cm-1 cm-1 3293 and 3363 are indicative of the presence of the stretching vibrations of the amine group cm-1 and 3363 cm-1 are indicative of the presence of the stretching vibrations of the amine group in the”
Effect of the Zwitterion, p(MAO-DMPA), on the Internal Structure, Fouling Characteristics, and Dye Rejection Mechanism of PVDF Membranes DOI: 10.3390/membranes10110323 -
confiance 1,0
“A strong peak at 3293 was designated as the N-H stretching vibration of the peptide groups and termed amide A.”
Extracellular vesicles derived from microgreens of Raphanus sativus L. var. caudatus Alef contain bioactive macromolecules and inhibit HCT116 cells proliferation DOI: 10.1038/s41598-022-19950-7 -
Hydroxyl (O-H) confiance 1,0
“Effect of virus titer on characteristic spectra peak height The most significant differences were found for the at 8 h.p.i cm-1, peak at 3293 The characteristic peaks of the BGMK cell line showed assigned to OH stretching (One-way 106 chang”
Lee-Montiel 等 - 2011 - Detection and quantification of poliovirus infecti DOI: 10.1186/1754-1611-5-16
Avez-vous un spectre avec cette bande ?
Téléchargez votre spectre FTIR et obtenez un rapport d'interprétation complet — attributions de pics avec citations bibliographiques, correspondances de bibliothèque et une chaîne de preuves avec évaluation de la confiance — en quelques secondes.