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
Ateb cyflym
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.
Aseiniadau grŵp swyddogaethol posibl
| Grŵp swyddogaethol | Ffeithiau ategol | Ffynonellau a ddyfynnwyd | Hyder uchaf |
|---|---|---|---|
| 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 |
Mae'r safle'n adlewyrchu tystiolaeth llenyddiaeth gronnwyd, nid rheol awdurdodol sengl. Cadarnhewch bob amser yn erbyn eich cyd-destun sampl.
Deunyddiau posibl
| Deunydd | Copaon ategol | Grwpiau sy'n gorgyffwrdd | Ffynonellau a ddyfynnwyd |
|---|---|---|---|
| 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 |
Mae deunyddiau'n cael eu dangos dim ond pan fydd yr un gronfa lenyddiaeth yn cefnogi'r band hwn ac o leiaf un brig nodweddiadol ychwanegol.
Rhesymeg sbectrwm
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.
Defnydd yn y byd go iawn
Mae'r math hwn o ymholiad yn gyffredin mewn adnabod polymer, sgrinio plastig anhysbys, datrys problemau QC, dilysu deunydd wedi'i ailgylchu, ac adolygiad o aseiniad copa wedi'i gefnogi gan lenyddiaeth.
Camgymeriadau cyffredin
- Trin un band ynysig fel prawf o ddeunydd heb wirio o leiaf un neu ddau gopa cefnogol.
- Anwybyddu gorgyffwrdd: gall grwpiau swyddogaethol lluosog gyfrannu ger yr un rhif ton.
- Hepgor dilysu pan fo ychwanegion, cymysgeddau, ocsideiddio, neu halogiad yn gallu ystumio'r sbectrwm.
Cyngor dilysu
Pan fo amwysedd yn parhau, dilyswch y rhagdybiaeth gyda DSC, GC-MS, neu TGA, yn enwedig ar gyfer cymysgeddau, samplau dirywiedig, a pholymerau llawn.
Llenyddiaeth y tu ôl i'r aseiniadau hyn
-
Alkyl C-H hyder 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 hyder 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 hyder 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) hyder 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 hyder 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 hyder 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.
Oes gennych sbectrwm gyda'r band hwn?
Llwythwch eich sbectrwm FTIR i fyny a chael adroddiad dehongli llawn — aseiniadau brig gyda chyfeiriadau llenyddiaeth, cyfateb llyfrgell, a chadwyn dystiolaeth â gradd hyder — mewn eiliadau.