What absorbs at 1787 cm⁻¹ in an FTIR spectrum?
A band near 1787 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 2 cited sources
Quick answer
A band near 1787 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 funktionelle gruppetildelinger
| Funktionel gruppe | Understøttende fakta | Citerede kilder | Højeste tillid |
|---|---|---|---|
| Ester | 2 | 2 | 1,0 |
| Carbonyl (C=O) | 2 | 2 | 1,0 |
| Carbohydrate | 1 | 1 | 1,0 |
| Methacrylate | 1 | 1 | 1,0 |
| Ketone | 1 | 1 | 1,0 |
| Carboxyl (COOH) | 1 | 1 | 1,0 |
| Amide | 1 | 1 | 1,0 |
| Acetate | 1 | 1 | 1,0 |
| Chlorine | 1 | 1 | 1,0 |
Rangering afspejler akkumulerede litteraturbeviser, ikke en enkelt autoritativ regel. Bekræft altid mod din prøvekontekst.
Spectrum logic
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 1787 cm⁻¹ is usually not enough for material identification by itself.
Real-world usage
This type of query is common in polymer identification, unknown plastic screening, QC troubleshooting, recycled-material verification, and literature-backed peak assignment review.
Common mistakes
- Treating one isolated band as proof of a material without checking at least one or two supporting peaks.
- Ignoring overlap: multiple functional groups can contribute near the same wavenumber.
- Skipping validation when additives, blends, oxidation, or contamination may distort the spectrum.
Verification advice
When ambiguity remains, validate the hypothesis with DSC, GC-MS, or TGA, especially for blends, degraded samples, and filled polymers.
Litteratur bag disse tildelinger
-
Chlorine tillid 1,0
“For all the matrices (CS:CL-CNC7:3-50%-AgNPs), new bands have appeared (1642 cm-1 and 1787 cm-1) showing a better interaction in the order of CL-WE-AgNPs rate: 5%, 10%, 40%, 50%, to 20%.”
Part B: Improvement of the Optical Properties of Cellulose Nanocrystals Reinforced Thermoplastic Starch Bio-Composite Films by Ex Situ Incorporation of Green Silver Nanoparticles from Chaetomorpha linum DOI: 10.3390/polym15092148 -
Carbonyl (C=O) tillid 1,0
“In the cm-1 case of f-MWNT 9, an ester carbonyl band at 1787 emerged due to an ester group on its”
Zhang 和 Yan - 2010 - Analytical strategies for characterizing the surfa DOI: 10.1007/s00216-009-2996-1.
Har du et spektrum med dette bånd?
Upload dit FTIR-spektrum og få en fuld tolkningsrapport — peak-tildelinger med litteraturhenvisninger, biblioteksmatch og en tillidsvurderet beviskæde — på få sekunder.