What absorbs at 1762 cm⁻¹ in an FTIR spectrum?
A band near 1762 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 3 cited sources
Possible functional-group assignments
| Functional group | Supporting facts | Cited sources | Top confidence |
|---|---|---|---|
| Carbonyl (C=O) | 2 | 2 | 1.0 |
| Carboxyl (COOH) | 2 | 2 | 1.0 |
| Methacrylate | 1 | 1 | 1.0 |
| Ketone | 1 | 1 | 1.0 |
| Ester | 1 | 1 | 1.0 |
| Amide | 1 | 1 | 1.0 |
| Acetate | 1 | 1 | 1.0 |
Ranking reflects accumulated literature evidence, not a single authoritative rule. Always confirm against your sample context.
Literature behind these assignments
-
Acetate confidence 1.0
“The absorption cm-1 C=O peak at 1762 corresponds to the stretching of the lactone of ascorbic acid and peak at cm-1”
Krishnan 等 - 2020 - Leaf Extract ofDillenia indicaas a Source of Selen DOI: 10.3390/coatings10070626 -
Carbonyl (C=O) confidence 1.0
“Amide I (urea) 1684 1683 1683 C=O carbonyl stretching vibration (intensity less) 1762”
Rangel-Vazquez 等 - 2014 - Spectroscopy Analyses of PolyurethanePolyaniline DOI: 10.1590/0104-1428.1496 -
Carboxyl (COOH) confidence 0.9
“Downshifted to 1736/1762 cm-1 in D2O, assigned to carboxyl group.”
Assignment of the CO-sensitive carboxyl group in mitochondrial forms of cytochrome c oxidase using yeast mutants DOI: 10.1016/j.bbabio.2012.03.036
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