What absorbs at 1778 cm⁻¹ in an FTIR spectrum?
A band near 1778 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 4 cited sources
Possible functional-group assignments
| Functional group | Supporting facts | Cited sources | Top confidence |
|---|---|---|---|
| Imide | 3 | 2 | 0.9 |
| Carbonyl (C=O) | 2 | 2 | 1.0 |
Ranking reflects accumulated literature evidence, not a single authoritative rule. Always confirm against your sample context.
Literature behind these assignments
-
Carbonyl (C=O) confidence 1.0
“Assigned to carbonyl groups”
Culica 等 - 2019 - Recyclable Polymer-Supported N-Hydroxyphthalimide DOI: 10.3390/ma12213585 -
Carbonyl (C=O) confidence 0.9
“Explicit assignment: 'carbonyl absorption peak centered at 1778'”
Locas 和 Yaylayan - 2008 - Further insight into thermally and pH-induced gene DOI: 10.1021/jf073055u -
Imide confidence 0.9
“Explicit assignment in text.”
Aly 等 - 2020 - Corrosion Resistance of Mild Steel Coated with Pht DOI: 10.3390/coatings10111114 -
Imide confidence 0.9
“Explicit assignment in text: 'imide I band at 1778' and 'asymmetrical C=O stretch vibration'.”
Feng 等 - 2019 - Flame Inhibition and Charring Effect of Aromatic P DOI: 10.3390/polym11010074
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