What absorbs at 2946 cm⁻¹ in an FTIR spectrum?
A band near 2946 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 6 cited sources
Brzi odgovor
A band near 2946 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.
Moguće dodjele funkcionalnih skupina
| Funkcionalna skupina | Potporni dokazi | Citirani izvori | Najveća pouzdanost |
|---|---|---|---|
| Alkyl C-H | 6 | 6 | 1,0 |
| Hydroxyl (O-H) | 1 | 1 | 1,0 |
| Methacrylate | 1 | 0 | 1,0 |
| Ketone | 1 | 0 | 1,0 |
| Ester | 1 | 0 | 1,0 |
| Carboxyl (COOH) | 1 | 0 | 1,0 |
| Carbonyl (C=O) | 1 | 0 | 1,0 |
| Amide | 1 | 0 | 1,0 |
| Acetate | 1 | 0 | 1,0 |
Rangiranje odražava akumulirane literaturne dokaze, a ne jedno autoritativno pravilo. Uvijek provjerite u kontekstu vašeg uzorka.
Mogući materijali
| Materijal | Potporni vrhovi | Preklapajuće skupine | Citirani izvori |
|---|---|---|---|
| polyurethane | 2946, 2270, 1700 | Alkyl C-H, Methacrylate | 1 |
| gelatin | 2946, 1652, 3300 | Methacrylate, Alkyl C-H, Hydroxyl (O-H) | 1 |
| saliva | 2946, 1648, 1664 | Alkyl C-H, Methacrylate | 1 |
Materijali su prikazani samo kada ista literatura podržava ovu traku i barem jedan dodatni karakteristični vrh.
Logika spektra
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 2946 cm⁻¹ is usually not enough for material identification by itself.
Upotreba u stvarnom svijetu
Ova vrsta upita uobičajena je u identifikaciji polimera, probiru nepoznate plastike, rješavanju problema u kontroli kvalitete, provjeri recikliranog materijala i pregledu dodjele vrhova potkrijepljenom literaturom.
Uobičajene pogreške
- Tretiranje jedne izolirane vrpce kao dokaza materijala bez provjere barem jednog ili dva podržavajuća pika.
- Zanemarivanje preklapanja: više funkcionalnih skupina može doprinositi u blizini istog valnog broja.
- Preskakanje validacije kada aditivi, mješavine, oksidacija ili kontaminacija mogu izobličiti spektar.
Savjet za provjeru
Kada nejasnoća ostane, validirajte hipotezu pomoću DSC, GC-MS ili TGA, posebno za mješavine, degradirane uzorke i punjene polimere.
Literatura iza ovih dodjela
-
Alkyl C-H pouzdanost 1,0
“This disappearance of the cm-1 cm-1 N-CH2 vibration bands at 2946 and 2811 indicated proton transfer between the N-CH2 (basic) of ARP and carboxylic groups (acidic) of SA.”
Multicomponent crystalline solid forms of aripiprazole produced via hot melt extrusion techniques: An exploratory study DOI: 10.1016/j.jddst.2021.102529. -
Alkyl C-H pouzdanost 1,0
“Protein 1662 cm-1 Stretching C-H Lipids 2946 Figure 3.”
Salivary ATR-FTIR Spectroscopy Coupled with Support Vector Machine Classification for Screening of Type 2 Diabetes Mellitus DOI: 10.3390/diagnostics13081396 -
Alkyl C-H pouzdanost 1,0
“CH asymmetric stretching”
Kavanaugh 等 - 2016 - Human mesenchymal stem cell behavior on segmented DOI: 10.1007/s10856-015-5654-5. -
Hydroxyl (O-H) pouzdanost 1,0
“Researchers reported that cm-1 cm-1 -OH stretch, 2945.51 and 2834.66 for C-H using the fungal strain decolorization of dyes with the cm-1 stretching of alkyl benzene, 1460.07 for -C-H wavelength range 250-700 nm could be degraded to cm-1 be”
Kiran 等 - 2019 - Lignin Degrading System of Phanerochaete chrysospo DOI: 10.15244/pjoes/89575 -
Alkyl C-H pouzdanost 0,9
“C-H stretching in alkane”
Characterization of plastic degrading bacteria isolated from sewage wastewater DOI: 10.1016/j.sjbs.2023.103628 -
Alkyl C-H pouzdanost 0,8
“Described as typical PU peaks”
Wang 等 - 2014 - Electrospun polyurethane-core and gelatin-shell co DOI: 10.1088/1758-5082/6/1/015002.
Imate li spektar s ovom vrpcom?
Prenesite svoj FTIR spektar i dobijte potpuno izvješće o interpretaciji — dodjele vrhova s literaturnim citatima, podudaranja knjižnice i lanac dokaza s ocjenom pouzdanosti — u sekundama.