What absorbs at 1233 cm⁻¹ in an FTIR spectrum?
A band near 1233 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 |
|---|---|---|---|
| Amide | 3 | 3 | 1.0 |
| C-O single bond | 1 | 1 | 0.9 |
| C n single bond | 1 | 1 | 0.9 |
Ranking reflects accumulated literature evidence, not a single authoritative rule. Always confirm against your sample context.
Literature behind these assignments
-
Amide confidence 1.0
“Explicit assignment in text”
Wang 等 - 2014 - Electrospun polyurethane-core and gelatin-shell co DOI: 10.1088/1758-5082/6/1/015002. -
Amide confidence 0.9
“assigned to amide III”
Casanova 等 - 2020 - Physico-chemical, structural and techno-functional DOI: 10.1016/j.ijbiomac.2020.04.047 -
C n single bond confidence 0.9
“C-N stretching vibration in β-sheet.”
Li 等 - 2023 - Effect of degumming degree on the structure and te DOI: 10.1038/s41598-023-33844-2 -
C-O single bond confidence 0.9
“Asymmetric stretching vibration of C-O-C.”
Sivasankari 等 - 2013 - Synthesis and Characterization of Thiophene Contai DOI: 10.14233/ajchem.2013.13514 -
Amide confidence 0.9
“Explicit assignment for G1 and G4.”
Yesiltas 等 - 2022 - Gelatin from Saithe (Pollachius virens) Skin Bioc DOI: 10.3390/md20120739 -
confidence 0.8
“Text states 'bands at 1233 and 1094 are antisym-'”
Ceylan 等 - 2023 - Combined Neutrase-Alcalase Protein Hydrolysates fr DOI: 10.1021/acsomega.2c07157 -
confidence 0.8
“Text: 'bands believed to be due to ... asymmetric O-C-O ... at 1233 and 1200'”
Larosa 等 - 2017 - Preparation and characterization of polycarbonate DOI: 10.3762/bjnano.8.203 -
confidence 0.6
“IR vibration modes are 1233 (β-phase context)”
Abdullah 等 - 2014 - Effect of annealing process on the phase formation DOI: 10.1063/1.4895187
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