What absorbs at 3120 cm⁻¹ in an FTIR spectrum?
A band near 3120 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 3120 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 |
|---|---|---|---|
| Hydroxyl (O-H) | 3 | 2 | 1,0 |
| N h | 2 | 2 | 1,0 |
| Alkyl C-H | 1 | 1 | 1,0 |
| Methacrylate | 1 | 1 | 1,0 |
| Ketone | 1 | 1 | 1,0 |
| Ester | 1 | 1 | 1,0 |
| Carboxyl (COOH) | 1 | 1 | 1,0 |
| Carbonyl (C=O) | 1 | 1 | 1,0 |
| Amide | 1 | 1 | 1,0 |
| Acetate | 1 | 1 | 1,0 |
| Secondary amine | 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.
Matériaux possibles
| Matériel | Pics de support | Groupes chevauchants | Sources citées |
|---|---|---|---|
| polyurethane | 3120, 2270, 1700 | Alkyl C-H, Methacrylate, N h | 1 |
| polysaccharide | 3120, 1637, 1320 | Methacrylate, Hydroxyl (O-H), Alkyl C-H | 1 |
| PANI | 3120, 2930, 1300 | Alkyl C-H, N h | 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 3120 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
-
Secondary amine confiance 1,0
“The N-H) of the thioamide and amide can be observed at asymmetric stretching vibration of the secondary amine (ν 3177cm-1 3120cm-1 and respectively.”
Adan 等 - 2014 - Synthesis, Characterization and Antibacterial Stud DOI: 10.1063/1.4895199 -
Hydroxyl (O-H) confiance 1,0
“The vibrational bands at between between 3680 cm-1 and 3120 cm-1 are due to O-H and N-H stretching and can be attributed to cm-1 cm-1 between 3680 cm-1 and 3120 cm-1 are due to O-H and N-H stretching and can be attributed to 3680 and 3120 a”
Self-Healable Supramolecular Vanadium Pentoxide Reinforced Polydimethylsiloxane-Graft- Polyurethane Composites DOI: 10.3390/polym11010041 -
Hydroxyl (O-H) confiance 1,0
“cm(cid:3)1 3000-3550 467 In the range, a strong and wide -OH absorption band can be seen, which corresponds to stretchingvibrations.Thepeaksat3120and2980cm(cid:3)1thatcan be observed in Fig.”
Synthesis and characterization of a novel ruthenium(ii) trisbipyridine complex magnetic nanocomposite for the selective oxidation of phenols DOI: 10.1039/c9ra05079e -
Acetate confiance 1,0
“The asymmetric and symmetric stretching CH3 C=O stretching of CH group and band vibrations were found at 3120 and 1670-1665 3”
Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (FTIR) and Artificial Neural Networks Applied to Investigate Quantitative Changes of Selected Soluble Biomarkers, Correlated with H. pylori Infection in Children and Presumable Consequent Delayed Growth DOI: 10.3390/jcm9123852 -
Alkyl C-H confiance 1,0
“LLM confirmed rule peak-group candidate”
Mucilage from Yellow Pitahaya (Selenicereus megalanthus)Fruit Peel: Extraction, Proximal Analysis, and Molecular Characterization DOI: 10.3390/molecules28020786 -
confiance 1,0
“The 3409cm-1 3120cm-1 1614cm-1 the peaks at peak at and are attributed to Nrepresents the N-H bend vibration.”
Zhu 等 - 2013 - Electrochemical Properties of PANI as Single Elect DOI: 10.1155/2013/940153 -
confiance 0,8
“Observed band assigned to C-H.”
Density Functional Theory and Molecular Docking Investigations of the Chemical and Antibacterial Activities for 1-(4-Hydroxyphenyl)-3-phenylprop-2-en-1-one DOI: 10.3390/molecules26123631
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.