What absorbs at 1271 cm⁻¹ in an FTIR spectrum?
Et bånd nær 1271 cm⁻¹ kan peke på flere funksjonelle grupper. Nedenfor er de mest sannsynlige tildelingene, rangert etter hvor mye publiserte bevis som støtter hver — hver enkelt sporbar til litteratur (DOI) og kryssvalidert mot våre 130 000+ referansespektre og kunnskapsgraf.
Backed by 8 cited sources
Raskt svar
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.
Mulige funksjonelle gruppe-tilordninger
| Funksjonell gruppe | Støttende fakta | Siterte kilder | Toppkonfidens |
|---|---|---|---|
| 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 |
Rangeringen gjenspeiler akkumulert litteraturbevis, ikke en enkelt autoritativ regel. Bekreft alltid mot prøvekonteksten din.
Mulige materialer
| Materiale | Støttetopper | Overlappende grupper | Siterte kilder |
|---|---|---|---|
| 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 |
Materialer vises kun når samme litteraturbase støtter dette båndet og minst en annen karakteristisk topp.
Spektrum-logikk
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.
Virkelig bruk
Denne typen forespørsel er vanlig i polymeridentifikasjon, screening av ukjent plast, feilsøking i kvalitetskontroll, verifisering av resirkulert materiale og litteraturstøttet gjennomgang av topptilordning.
Vanlige feil
- Behandle ett isolert bånd som bevis på et materiale uten å sjekke minst en eller to støttende topper.
- Ignorerer overlapping: flere funksjonelle grupper kan bidra nær samme bølgetall.
- Hopp over validering når tilsetningsstoffer, blandinger, oksidasjon eller forurensning kan forvrenge spekteret.
Verifiseringsråd
Når tvetydighet gjenstår, valider hypotesen med DSC, GC-MS eller TGA, spesielt for blandinger, nedbrutte prøver og fylte polymerer.
Litteratur bak disse tilordningene
-
Lignin konfidens 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) konfidens 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 konfidens 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 konfidens 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 konfidens 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 konfidens 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 -
konfidens 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 konfidens 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
Har du et spektrum med denne bånden?
Last opp FTIR-spektrumet ditt og få en full tolkningsrapport — topptilordninger med litteraturhenvisninger, bibliotekssøk og en konfidensvurdert beviskjede — på sekunder.