What absorbs at 2119 cm⁻¹ in an FTIR spectrum?
A band near 2119 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 |
|---|---|---|---|
| Metal oxygen | 2 | 1 | 1.0 |
| Adsorbed carbon monoxide | 2 | 1 | 1.0 |
| Methacrylate | 1 | 1 | 1.0 |
| Ketone | 1 | 1 | 1.0 |
| Ester | 1 | 1 | 1.0 |
| Carboxyl (COOH) | 1 | 1 | 1.0 |
| Carbonyl (C=O) | 1 | 1 | 1.0 |
| Amide | 1 | 1 | 1.0 |
| Acetate | 1 | 1 | 1.0 |
| C#c | 1 | 1 | 1.0 |
| Alkyl C-H | 1 | 0 | 1.0 |
Ranking reflects accumulated literature evidence, not a single authoritative rule. Always confirm against your sample context.
Literature behind these assignments
-
Adsorbed carbon monoxide confidence 1.0
“It shows that CO adsorption gives strong bands at 2119 and 2079 cm-1 attributed to CO adsorbed”
Effect of Pt cocatalyst in Pt/TiO2 studied by in situ FTIR of CO adsorption DOI: 10.1016/S1872-2067(14)60172-8 -
C#c confidence 1.0
“The band which appeared at 2119 cm-1 spectroscopy is absorption spectroscopy used to conindicates the presence of an alkyne group.”
Evaluation of biological synthesized platinum nanoparticles using Ononidis radix extract on the cell lung carcinoma A549 DOI: 10.1007/s10544-019-0424-7 -
Acetate confidence 1.0
“The spectra shows a distinct peak at 2119 representing C=O stretching that was assigned for CO.”
Jameel 等 - 2017 - Heavy fuel oil pyrolysis and combustion Kinetics DOI: 10.1016/j.jaap.2017.08.008
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