What absorbs at 1779 cm⁻¹ in an FTIR spectrum?
A band near 1779 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
Stutt svar
A band near 1779 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.
Mögulegar úthlutun virkra hópa
| Virkur hópur | Stuðningsstaðreyndir | Tilvitnuð heimildir | Mesta öryggi |
|---|---|---|---|
| Carbonyl (C=O) | 5 | 5 | 1,0 |
| Imide | 2 | 2 | 1,0 |
| Ring structure | 1 | 1 | 1,0 |
| Alkyl C-H | 1 | 1 | 1,0 |
Röðun endurspeglar uppsöfnuð ritrýnisgögn, ekki eina valdboðsreglu. Staðfestu alltaf í samhengi við sýnið þitt.
Möguleg efni
| Efni | Stuðningstindar | Skarast hópar | Tilvitnuð heimildir |
|---|---|---|---|
| polyimide | 1779, 1720, 1778 | Carbonyl (C=O), Imide | 1 |
Efni birtast aðeins þegar sama bókmenntasafn styður þessa band og að minnsta kosti einn viðbótar einkennandi hámark.
Rófrök
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 1779 cm⁻¹ is usually not enough for material identification by itself.
Raunveruleg notkun
Þessi tegund fyrirspurna er algeng við auðkenningu fjölliða, skimun óþekktra plasttegunda, bilanaleit í gæðaeftirliti, staðfestingu endurunnins efnis og bókmenntabakkaða endurskoðun á hápunktum.
Algeng mistök
- Meðhöndla eina einangraða öldulengd sem sönnun á efni án þess að athuga að minnsta kosti einn eða tvo stuðningstoppa.
- Hunsa skörun: mörg virkir hópar geta lagt sitt af mörkum nálægt sömu bylgjutölunni.
- Að sleppa staðfestingu þegar aukefni, blöndur, oxun eða mengun geta brenglað litrófið.
Staðfestingarráðgjöf
Þegar tvíræðni er eftir, staðfestu tilgátuna með DSC, GC-MS eða TGA, sérstaklega fyrir blöndur, niðurbrotin sýni og fylltar fjölliður.
Ritlist á bak við þessar úthlutanir
-
Imide öryggi 1,0
“the unaged CBR 320/328 composites reveal three imide carbonyl peaks at 1779, 1728 and 1712 These peaks may be assigned to the symmetric and asymmetric stretches of an unsaturated imide (1779 and 1728 cm(cid:2)1)”
Fox 等 - 2004 - Investigation of failure mechanisms in aged aerosp DOI: 10.1016/j.engfailanal.2003.05.010 -
Carbonyl (C=O) öryggi 1,0
“Fourier Transt Copyright: American Scientific Publishers cm-1, form Infrared Spectroscopy (FTIR) spectra shows two new absorbance peaks at 1779 and 1851 which i Delivered by Ingenta c correspond to symmetrical and asymmetrical stretching vi”
Compatibilization effect of EVA-g-MAH on mechanical, morphological and rheological properties of recycled PC/ABS blend DOI: 10.1166/mex.2014.1198 -
Alkyl C-H öryggi 1,0
“Peaks that can only be assigned to polyimide in the blend include the methyl group C-H stretching cm-1), cm-1), C=O (symmetric stretching) (1779 C=O (anti-symetric stretching) (2957-2863 cm-1),”
Maab 等 - 2009 - SPEEKPolyimide Blends for Proton Conductive Membr DOI: 10.1002/fuce.200800121 -
Carbonyl (C=O) öryggi 1,0
“In the FTIR cm(cid:3)1 spectrum strong absorption bands appeared at 1779 due to the asymmetric vibration of the carbonyl imide ring, at 1719 cm(cid:3)1 attributed to the symmetric vibration of carbonyl imide”
Serbezeanu 等 - 2016 - Phosphorus-containing polyimide fibers and their t DOI: 10.1039/c6ra06497c -
Carbonyl (C=O) öryggi 0,95
“Explicit assignment: 'the C=O (of SMA) peak at a wavelength of 1779'”
The effect of Styrene Maleic Anhydride on the microstructure evolution of PSF-based membrane prepared by thermal-induced phase separation method DOI: 10.1016/j.mtcomm.2019.100687
Ertu með róf með þessu bandi?
Hladdu upp FTIR-rófinu þínu og fáðu fulla túlkunarskýrslu — toppúthlutun með tilvitnunum í ritrýni, bókasamsvörun og sönnunarkeðju með öryggismati — á nokkrum sekúndum.