What absorbs at 809 cm⁻¹ in an FTIR spectrum?
A band near 809 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 8 cited sources
Snabbt svar
A band near 809 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 |
|---|---|---|---|
| Methacrylate | 4 | 3 | 1,0 |
| Acetate | 4 | 3 | 1,0 |
| Alkyl C-H | 4 | 3 | 1,0 |
| Methoxy (OCH3) | 3 | 3 | 1,0 |
| C-O single bond | 3 | 3 | 1,0 |
| Silicon-oxygen (Si-O) | 2 | 2 | 1,0 |
| Metal oxygen | 2 | 2 | 1,0 |
| Amide | 2 | 1 | 1,0 |
| C-S single bond | 1 | 1 | 1,0 |
| Silicon (Si) | 1 | 1 | 1,0 |
| Aromatic ring | 1 | 1 | 1,0 |
| Nitrogen heterocycle | 1 | 1 | 1,0 |
| N h | 1 | 1 | 1,0 |
| Secondary amine | 1 | 1 | 1,0 |
| C n single bond | 1 | 1 | 1,0 |
| Siloxane (Si-O-Si) | 1 | 1 | 1,0 |
| Silicon carbon | 1 | 1 | 1,0 |
| Carbohydrate | 1 | 1 | 0,8 |
| Ketone | 1 | 0 | 1,0 |
| Ester | 1 | 0 | 1,0 |
| Carboxyl (COOH) | 1 | 0 | 1,0 |
| Carbonyl (C=O) | 1 | 0 | 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 |
|---|---|---|---|
| silica | 809, 1100, 1080 | Alkyl C-H, Methacrylate, Acetate | 1 |
| nanotubes | 809, 1735, 1630 | Alkyl C-H, Methacrylate, Acetate | 1 |
| lignin | 809, 1035, 1510 | Alkyl C-H, Methacrylate, Acetate | 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 809 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
-
Metal oxygen förtroende 1,0
“and iii)the appearanceof newRaman lines at 809 cm-1, 710 and 809 which are attributed to the W-O vibrational mode in WO [28].”
Single-walled carbon nanotubes functionalized with polydiphenylamine as active materials for applications in the supercapacitors field DOI: 10.1016/j.diamond.2012.12.006 -
Silicon carbon förtroende 1,0
“Correspond to Si-C bonds.”
Optical and photoelectrochemical properties of nitrogen-doped a-SiC thin films deposited by reactive DOI: 10.1080/2374068X.2021.1890420 -
Metal oxygen förtroende 1,0
“10 a-b), peaks at 809, 811 and 812 cm-1 mixtures, MNP-PCP shifted to 814 which assigned to As-O [35].”
Enhanced arsenic (iii) adsorption from aqueous solution by magnetic pine cone biomass DOI: 10.1016/j.matchemphys.2018.09.067 -
förtroende 1,0
“The cm-1 intense band at 1069 corresponds to the Si-O-Si symmetric stretching vibration, cm-1 whereas the Si-O-Si anti-symmetric stretching band is observed at 809 [24,25].”
Vibrational spectroscopic study of pure and silica-doped sulfonated poly(ether ether ketone) membranes DOI: 10.1016/j.saa.2014.12.004 -
Alkyl C-H förtroende 1,0
“The spectrum of porous graphene nanosheets is represented by the cm-1, cm-1, cm-1 cm-1, peaks at 809 1636 2344 and 3309 resulting from C-H bonding, C=C conjugation, C-N band and N-H extending vibrations.”
An Amperometric Acetylcholine Biosensor Based on Co-Immobilization of Enzyme Nanoparticles onto Nanocomposite DOI: 10.3390/bios13030386 -
Acetate förtroende 1,0
“[60] assigned the spectral features of pure chlorogenic acid isomer standards as follows: The peak at cm-1 cm-1 809 was attributed to cyclohexane C-O twisting;”
Durazzo 等 - 2018 - Qualitative Analysis of Traditional Italian Dishes DOI: 10.3390/su10114112 -
förtroende 1,0
“ESI-MS molecular-ion peak 809.21, corresponding to H+ + 1H [Zn(L3) ].”
Gusev 等 - 2020 - Synthesis, Photoluminescence and Electrical Study DOI: 10.3390/ma13245698 -
Acetate förtroende 1,0
“cm-1) cm-1) 1330-1326 [30], a C-O-C band center position (1025 [31], and C-O-C vibrations lignin, there is a syringyl (S) at 809 cm-1.”
Mesoporous Manganese Oxide/Lignin-Derived Carbon for High Performance of Supercapacitor Electrodes DOI: 10.3390/molecules26237104
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