What absorbs at 1747 cm⁻¹ in an FTIR spectrum?
A band near 1747 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
Possible functional-group assignments
| Functional group | Supporting facts | Cited sources | Top confidence |
|---|---|---|---|
| Carbonyl (C=O) | 5 | 5 | 1.0 |
| Ester | 1 | 1 | 0.7 |
| Protein | 1 | 1 | 0.7 |
| Lipid | 1 | 1 | 0.7 |
Ranking reflects accumulated literature evidence, not a single authoritative rule. Always confirm against your sample context.
Literature behind these assignments
-
confidence 1.0
“Explicitly assigned to lipid ester carbonyl.”
Chatchawal 等 - 2021 - Detection of Human Cholangiocarcinoma Markers in S DOI: 10.3390/cancers13205109 -
Carbonyl (C=O) confidence 1.0
“PLA C=O group at 1747 cm-1”
Harris 等 - 2021 - Partial Polymer Blend for Fused Filament Fabricati DOI: 10.3390/polym13193353 -
Carbonyl (C=O) confidence 0.9
“Characteristic absorption at 1747 cm-1 from propionylation.”
Li 等 - 2021 - Manipulation of the internal structure of starch b DOI: 10.1016/j.carbpol.2021.118390 -
Carbonyl (C=O) confidence 0.9
“Explicit assignment: '1747 showed C-O and C=O group of cellulose'”
Nasir 等 - 2017 - Nanostructure and Property of Electrospun SiO2-Cel DOI: 10.1016/j.egypro.2016.12.133 -
confidence 0.9
“Explicit assignment in text: 'group at 1747.2 cm-1'.”
Diaz-Pedraza 等 - 2021 - Effect of potassium sorbate as an interface agent DOI: 10.24275/rmiq/Alim1999 -
Carbonyl (C=O) confidence 0.9
“strain vibration of C=O group”
Widjaja 等 - 2023 - Poly lactic acid production using the ring opening DOI: 10.1016/j.heliyon.2023.e17985 -
Carbonyl (C=O) confidence 0.7
“Implied process of hydrogen bonding decomposition”
Lai 和 Wu - 2008 - Investigation on the conformations of AOT in water DOI: 10.1016/j.molstruc.2008.01.017 -
Lipid confidence 0.7
“Region 1462-1747 cm-1 attributed to lipid/protein regions.”
Bernardes-Oliveira 等 - 2020 - Spectrochemical differentiation in gestational dia DOI: 10.1038/s41598-020-75539-y
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