What absorbs at 736 cm⁻¹ in an FTIR spectrum?
A band near 736 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 7 cited sources
Réponse rapide
A band near 736 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) | 2 | 2 | 1,0 |
| Methacrylate | 2 | 2 | 1,0 |
| C-O single bond | 2 | 2 | 1,0 |
| Acetate | 2 | 2 | 1,0 |
| Alkyl C-H | 2 | 2 | 1,0 |
| Carbonyl (C=O) | 2 | 1 | 1,0 |
| C c single bond | 1 | 1 | 1,0 |
| Ketone | 1 | 1 | 1,0 |
| Ester | 1 | 1 | 1,0 |
| Carboxyl (COOH) | 1 | 1 | 1,0 |
| Amide | 1 | 1 | 1,0 |
| Nitrogen heterocycle | 1 | 1 | 1,0 |
| Aromatic ring | 1 | 1 | 1,0 |
| Silicon (Si) | 1 | 1 | 1,0 |
| Carbonate | 1 | 0 | 0,6 |
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 736 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
-
Silicon (Si) confiance 1,0
“smaller peaks at 736 and 697 both ascribed to Si-phenyl 6.”
Modification of Chrysotile Surface by Organosilanes: An IR–Photoacoustic Spectroscopy Study DOI: 10.1006/jcis.2001.7524 -
Nitrogen heterocycle confiance 1,0
“LLM confirmed rule peak-group candidate”
Wang 等 - 2014 - Target Synthesis of a Novel Porous Aromatic Framew DOI: 10.6023/A14020121 -
Alkyl C-H confiance 1,0
“Bands at 736 and 873 in OneFill suggested cm-1, cm-1, cm-1, the presence of C-H bending.”
Assiry 等 - 2023 - Microstructural and Elemental Characterization of DOI: 10.3390/app13074517 -
Alkyl C-H confiance 1,0
“In the FTIR spectra of the NCE, 1090, 2080, 3070, and 4060 polymers, the 729-, 744-, 744-, 729-, In the FTIR spectra of the NCE, 1090, 2080, 3070, and 4060 polymers, the 729-, 744-, 744-, 729-, and 736-cm-1 and 736-cm-1 peaks are δCH (out-o”
Li 等 - 2019 - Blends of Cyanate Ester and Phthalonitrile-Polyhed DOI: 10.3390/polym11010054 -
Acetate confiance 1,0
“Signals at 736 cm-1, 1212 cm-1 and 1047 cm-1 corresponded to 1047 and 900 Signals at 736 1212 and 1047 corresponded to -C=O, -C-C-Oand -C-O groups, respectively, representing the characteristics of CTA -C=O, -C-C-Oand -C-O groups, respectiv”
Membrane Fouling Behavior of Forward Osmosis for FruitJuice Concentration DOI: 10.3390/membranes11080611 -
Acetate confiance 1,0
“Further, a furan ring was and out-of-plane wagging deformation were detected at 3327 Further, a furan ring detected by characteristic peaks at 1011 and 736 cm-1 that were caused by C-O-C antisymcm-1”
Wen 等 - 2021 - Development of Low-Viscosity and High-Performance DOI: 10.3390/ma -
confiance 0,9
“Explicit assignment in text.”
Uner 等 - 2016 - Centaurea solstitialis and Silybum marianum weeds DOI: 10.1007/s13726-015-0396-2
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