What absorbs at 691 cm⁻¹ in an FTIR spectrum?
A band near 691 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 5 cited sources
Ateb cyflym
A band near 691 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 |
|---|---|---|---|
| Alkene (C=C) | 1 | 1 | 1.0 |
| Imide | 1 | 1 | 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 |
| Metal oxygen | 1 | 1 | 1.0 |
| Carboxyl (COOH) | 1 | 1 | 0.9 |
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 |
|---|---|---|---|
| polydopamine | 691, 1543, 1707 | Methacrylate, Methoxy (OCH3) | 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 691 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
-
Metal oxygen hyder 1.0
“The intense band at 691.17 corresponds to 691.17 cm-1 corresponds to the Ce-O stretching vibrations [11];”
Synthesis of Lipase-Immobilized CeO2 Nanorods as Heterogeneous Nano-Biocatalyst for Optimized Biodiesel Production from Eruca sativa Seed Oil DOI: 10.3390/catal10020231 -
Imide hyder 1.0
“The disappearance of band at 691 The T values of the polymer are in the range of 199due to maleimide C=C bond confirms completion of the addig”
Sivasankari 等 - 2013 - Synthesis and Characterization of Thiophene Contai DOI: 10.14233/ajchem.2013.13514 -
hyder 0.9
“para-disubstituted aromatic ring”
Azubuike 等 - 2020 - Evaluation of super-disintegrant potential of acid DOI: 10.4314/tjpr.v19i3.1 -
Carboxyl (COOH) hyder 0.9
“Text: 'sharp peaks at 503, 606 and 691 are due to the carboxylic group.'”
Priya 和 Azhagan - 2023 - Influence of succinic acid species on structural, DOI: 10.15251/DJNB.2023.181.55 -
hyder 0.8
“Band above 691 cm-1 attributed to bending of BO units.”
Density of Bismuth Boro Zinc Glasses Using Machine Learning Techniques DOI: 10.1007/s10904-021-02183-y
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.