What absorbs at 2141 cm⁻¹ in an FTIR spectrum?
A band near 2141 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 5 cited sources
Possible functional-group assignments
| Functional group | Supporting facts | Cited sources | Top confidence |
|---|---|---|---|
| Adsorbed carbon monoxide | 2 | 2 | 1.0 |
| C#c | 1 | 1 | 1.0 |
| Silicon hydride | 1 | 1 | 1.0 |
| Methoxy (OCH3) | 1 | 1 | 1.0 |
| Methacrylate | 1 | 1 | 1.0 |
| C-O single bond | 1 | 1 | 1.0 |
| Acetate | 1 | 1 | 1.0 |
| Alkyl C-H | 1 | 1 | 1.0 |
| N n bond | 1 | 1 | 1.0 |
| Secondary amine | 1 | 1 | 1.0 |
| C n single bond | 1 | 1 | 1.0 |
| Amide | 1 | 1 | 1.0 |
| Carboxyl (COOH) | 1 | 1 | 1.0 |
| Hydroxyl (O-H) | 1 | 1 | 1.0 |
Ranking reflects accumulated literature evidence, not a single authoritative rule. Always confirm against your sample context.
Literature behind these assignments
-
Hydroxyl (O-H) confidence 1.0
“2325.00 2349.47, 2817.79, 2124.28, 1905.70, 1444.61, 1123.54, and 529.99 were 2337.64 assigned to O-H stretching, alcohol, O-H stretching, carboxylic acid, - - 2140.59 2124.28 carbodiimide (N=C--N C-- = N N stretching, allene, C-H bending,”
Preparation and characterization of activated carbon from agricultural wastes and their ability to remove chlorpyrifos from water DOI: 10.1016/j.toxrep.2023.01.011 -
Silicon hydride confidence 1.0
“and SiH stretching vibration at 2141 The absorption peaks position and identification of SiH bonds in the spectral range 3 x cm-1 from 2050 to 2150 are listed in Tab.”
Kralik 和 Kopani - 2023 - Analysis of porous silicon structures using FTIR a DOI: 10.2478/jee-2023-0028 -
C#c confidence 1.0
“At peak with wave numbers 2140.99 cm-1 and 2059.98 , corresponds to the absorption caused by the triple bonds of C≡C (alkaline type cm-1”
Maulida 等 - 2018 - Utilization of mango seed starch in manufacture of DOI: 10.1088/1748-0221/5/10/P10010/pdf -
Adsorbed carbon monoxide confidence 1.0
“The relevant features of the spectrum of CO adsorbed at 60 K (Figure 3) are: a) a broad and highly cm-1 cm-1, reversible band at 2141 due to physically adsorbed CO;”
Mino 等 - 2012 - Particles Morphology and Surface Properties As Inv DOI: 10.1021/jp303942h -
Adsorbed carbon monoxide confidence 1.0
“The relevant features of the spectrum of CO adsorbed at 60 K (Figure 3) are: a) a broad and highly cm-1 cm-1, reversible band at 2141 due to physically adsorbed CO;”
Mino 等 - 2013 - Rutile Surface Properties Beyond the Single Crysta DOI: 10.1021/jp401916q
Have a spectrum with this band?
Upload your FTIR spectrum and get a full interpretation report — peak assignments with literature citations, library matches, and a confidence-rated evidence chain — in seconds.
Interpret my spectrum