What absorbs at 2161 cm⁻¹ in an FTIR spectrum?
A band near 2161 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 |
|---|---|---|---|
| Nitrile | 1 | 1 | 1.0 |
| Silanol (Si-OH) | 1 | 1 | 1.0 |
| Adsorbed carbon monoxide | 1 | 1 | 1.0 |
| C#c | 1 | 1 | 1.0 |
| Alkyl C-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
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Alkyl C-H confidence 1.0
“The absorption characteristics of chitosan with OH stretching were found at 3002 cm-1, C-H at 2161 cm-1, and C=O at”
Synthesis and Optimization of Superhydrophilic-Superoleophobic Chitosan–Silica/HNT Nanocomposite Coating for Oil–Water Separation Using Response Surface Methodology DOI: 10.3390/nano12203673 -
C#c confidence 1.0
“3276 Strong, broad Alcohol Alkyne C≡C terminal alkyne (monosubstiOH stretch 2161 Weak”
The Antimicrobial Activities of Silver Nanoparticles from Aqueous Extract of Grape Seeds against Pathogenic Bacteria and Fungi DOI: 10.3390/molecules26196081 -
Adsorbed carbon monoxide confidence 1.0
“cm-1) other two bands at higher frequencies (2161 and 2152 required more time for complete The other two bands at higher frequencies (2161 cm-1 and 2152 cm-1) required more time for complete desorption, and for this reason they can be assig”
Atzori 等 - 2020 - Adsorption Properties of Ce-5(BDC)(7.5)(DMF)(4) MO DOI: 10.3390/inorganics8020009 -
Silanol (Si-OH) confidence 1.0
“The cm-1 remaining band at 2161 is related to silanol groups present in large quantity in Mn 2.0SiBEA in line with earlier”
Influence of the nature and environment of manganese in Mn-BEA zeolites on NO conversion in selective catalytic reduction with ammonia DOI: 10.1039/C7CP02096A -
Nitrile confidence 1.0
“ice is warmed, a nitrile band at 2161 AAN is diluted in water ice, a large amount of AAN is driven”
Borget 等 - 2012 - Aminoacetonitrile characterization in astrophysica DOI: 10.1051/0004-6361/201218949
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