What absorbs at 747 cm⁻¹ in an FTIR spectrum?
A band near 747 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
Snabbt svar
A band near 747 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.
Möjliga identifieringar av funktionella grupper
| Funktionell grupp | Stödjande fakta | Citerade källor | Högsta förtroende |
|---|---|---|---|
| Metal oxygen | 4 | 4 | 1,0 |
| Alkyl C-H | 3 | 3 | 1,0 |
| Aromatic ring | 2 | 2 | 1,0 |
| Carbonyl (C=O) | 2 | 2 | 1,0 |
| Methacrylate | 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 |
| Acetate | 1 | 1 | 1,0 |
Rankingen speglar ackumulerade litteraturbevis, inte en enda auktoritativ regel. Bekräfta alltid mot din provkontext.
Möjliga material
| Material | Stödjande toppar | Överlappande grupper | Citerade källor |
|---|---|---|---|
| nanotube | 747, 1540, 1080 | Alkyl C-H | 1 |
| HDPE | 747, 1369, 1216 | Alkyl C-H, Aromatic ring, Carbonyl (C=O) | 1 |
| LDPE | 747, 1720, 1737 | Alkyl C-H, Carbonyl (C=O), Aromatic ring | 1 |
Material visas endast när samma litteraturpool stöder detta band och minst en ytterligare karakteristisk topp.
Spektrumlogik
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 747 cm⁻¹ is usually not enough for material identification by itself.
Användning i verkligheten
Denna typ av fråga är vanlig inom polymeridentifiering, screening av okänd plast, felsökning av kvalitetskontroll, verifiering av återvunnet material och litteraturstödd toppidentifieringsgranskning.
Vanliga misstag
- Behandla ett isolerat band som bevis på ett material utan att kontrollera minst en eller två stödjande toppar.
- Ignorerar överlapp: flera funktionella grupper kan bidra nära samma vågtal.
- Hoppa över validering när tillsatser, blandningar, oxidation eller föroreningar kan förvränga spektrat.
Verifieringsråd
När oklarhet kvarstår, validera hypotesen med DSC, GC-MS eller TGA, särskilt för blandningar, nedbrutna prover och fyllda polymerer.
Litteratur bakom dessa identifieringar
-
Carbonyl (C=O) förtroende 1,0
“Therefore, the ging band appears between 850 and regions, even though only one carbonyl group is present, prob746cm-1 747cm-1 in the infrared and in Raman is band at ably due to Fermi resonance.”
Arjunan 等 - 2007 - Fourier transform infrared and Raman spectral assi DOI: 10.1016/j.saa.2006.09.044 -
Aromatic ring förtroende 1,0
“The FTIR spectrum of FNTs/FU conjugated with FA/MNPs showed peaks at wavelengths of 747, 878, 623, 1000-1400, corresponding to benzene vibration of FF, CF=CH of FU, Fe-O, fluoro of FU respectively (Fig.”
Covalent diphenylalanine peptide nanotube conjugated to folic acid/magnetic nanoparticles for anti-cancer drug delivery DOI: 10.1016/j.jddst.2017.06.005 -
Metal oxygen förtroende 1,0
“LLM confirmed rule peak-group candidate”
Retnoningtyas 等 - 2022 - Synthesis and Characterization of Methionine-Funct DOI: 10.33263/BRIAC125.58455859 -
Acetate förtroende 1,0
“show C-H bond stretching vibrations, whereas the peak at specifies 1,747cm-1 cm-1 C=O stretch, and 1,769 depicts CH2/ 1,726cm-1 CH3 stretch in the EVA particle sample.”
Hossain 等 - 2023 - First evidence of microplastics and their characte DOI: 10.3389/fenvs.2023.1232931 -
Metal oxygen förtroende 1,0
“LLM confirmed rule peak-group candidate”
Nadeem 等 - 2022 - Stability Analysis of Fe3O4-OA-MWCNT Nanocomposite DOI: 10.1155/2022/1859698 -
förtroende 1,0
“An absorption peak appeared at cm-1 747 which could be assigned to Al-O bond of Al 2O 3.”
Efficient removal of 2-chlorophenol from aqueous solution using TiO2 thin films/alumina disc as photocatalyst by pulsed laser deposition DOI: 10.1007/s13201-021-01372-x -
Alkyl C-H förtroende 1,0
“The peak at 747 is assigned to the to cm-1 C-H bending vibrations of the benzene [35].”
Thabede 等 - 2023 - Synthesis of lanthanum metal organic framework usi DOI: 10.15251/DJNB.2023.181.157
Har du ett spektrum med detta band?
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