What absorbs at 1271 cm⁻¹ in an FTIR spectrum?
A band near 1271 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
Brzi odgovor
A band near 1271 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 |
|---|---|---|---|
| C-O single bond | 5 | 4 | 1,0 |
| Methoxy (OCH3) | 4 | 3 | 1,0 |
| Methacrylate | 4 | 3 | 1,0 |
| Acetate | 4 | 3 | 1,0 |
| Ester | 2 | 2 | 1,0 |
| Ketone | 1 | 1 | 1,0 |
| Carboxyl (COOH) | 1 | 1 | 1,0 |
| Carbonyl (C=O) | 1 | 1 | 1,0 |
| Amide | 1 | 1 | 1,0 |
| Fluorine (C-F) | 1 | 1 | 1,0 |
| N h | 1 | 1 | 1,0 |
| Hydroxyl (O-H) | 1 | 1 | 1,0 |
| Lignin | 1 | 1 | 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 |
|---|---|---|---|
| polyimide | 1271, 1720, 1778 | Methacrylate, Acetate | 1 |
| PVC | 1271, 834, 1195 | Methoxy (OCH3), Methacrylate, Acetate | 1 |
| cellulose | 1271, 1735, 1650 | Acetate, Methacrylate, C-O single bond | 1 |
| HDPE | 1271, 1369, 1216 | Methacrylate, Acetate, Methoxy (OCH3) | 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 1271 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
-
Lignin pouzdanost 1,0
“The most characteristic vibrations of lignin correspond to thoseofaromaticringsatapproximately1599and1509cm(cid:2)1.Thetypicalbandsassignedto identifiedat1271and1216cm(cid:2)1(guaiacylringbreathing) guaiacyl(G)moietieswere and cm(cid:2)1 cm”
Synthesis and characterization of lignin–melamine–formaldehyde resin DOI: 10.1177/0892705716632856 -
Hydroxyl (O-H) pouzdanost 1,0
“The peak at about 1271 and 3478 were due in CP2, TP1, to OH stretching vibration of free acid groups and N-H TP2 and TP3 was assigned to C-F vibration.”
Purushothaman 和 Bilal - 2014 - Development and characterization of homo, co and t DOI: 10.1515/polyeng-2013-0167 -
Acetate pouzdanost 1,0
“(10/90) 10/90 6/94 0.18 cm-1, teristic of ester groups, and another typical band at 1271 assigned to the C-O-C (20/80)”
Isosorbide and 2,5-Furandicarboxylic Acid Based (Co)Polyesters: Synthesis, Characterization, and Environmental Degradation DOI: 10.3390/polym14183868 -
Acetate pouzdanost 1,0
“The band at 1123 cm-1 corresponds to planar cm-1 at 1327 belongs to the skeletal vibrations of the syringyl ring with the C-O stretching bending vibrations of the C-H syringyl aromatic rings, and the C-O stretching vibrations bands around 1”
An Efficient Method of Birch Ethanol Lignin Sulfation with a Sulfaic Acid-Urea Mixture DOI: 10.3390/molecules27196356 -
Ester pouzdanost 1,0
“Furthermore, the bands at cm-1 cm-1 cm-1 1271 and 1724 are characteristic of the ester group and the band at 729 represents the cm-1 aromatic ring of the phthalate group [37].”
Nolasco 等 - 2022 - Morphology, Chemical Characterization and Sources DOI: 10.21203/rs.3.rs-1166452/v1 -
Acetate pouzdanost 1,0
“the C-O stretching vibration peak at 1271 and cm-1, the aromatic skeleton (=C-H) stretching vibration at 3000-3020 which was coincided with decrease of O and H”
Xu 和 Li - 2017 - Effect of High-pressure on Pine Sawdust Pyrolysis DOI: 10.1063/1.4992933 -
pouzdanost 0,9
“Explicit assignment: '1271 (s, ester stretch C-O)'”
Rezende 等 - 2020 - Efficient internal plasticization of poly(vinyl ch DOI: 10.1016/j.polymer.2020.122473 -
C-O single bond pouzdanost 0,7
“Band at approx. 1271 cm-1 assigned to C-C(=O)-O.”
Chemometric approach to characterization of the selected grape seed oils based on their fatty acids composition and FTIR spectroscopy DOI: 10.1038/s41598-021-98763-6
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.