What absorbs at 2155 cm⁻¹ in an FTIR spectrum?
A band near 2155 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 |
|---|---|---|---|
| Hydroxyl (O-H) | 3 | 2 | 1.0 |
| Adsorbed carbon monoxide | 2 | 0 | 1.0 |
| Silanol (Si-OH) | 1 | 1 | 1.0 |
| Silicon-oxygen (Si-O) | 1 | 0 | 1.0 |
| Silicon (Si) | 1 | 0 | 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
“Physisorbed CO results in a band at 2140 cm-1, whereas CO interacting with surface OH groups gives rise to a band at 2155 while cm-1 cm-1 another massif from 2180 to 2245 accounts for CO interacting with Lewis cm-1”
Upgrading the PtCu intermetallic compounds: The role of Pt and Cu in the alloy DOI: 10.1016/j.cattod.2019.11.026 -
Silanol (Si-OH) confidence 1.0
“Spectra relative to 80P, 80H correspond to H-bonded cm-1, and 30H samples show a signal, centred at 2155 ascribed to the stretching mode of CO interacting with silanols.”
Erigoni 等 - 2016 - Creating Accessible Active Sites in Hierarchical M DOI: 10.1038/ncomms9633. -
Hydroxyl (O-H) confidence 1.0
“on Downloaded B10 cm(cid:2)1 cm(cid:2)1 with the surface OH groups, whereas the band at 2155 in comparison with those from the non-chlorinated Published sample.”
Farra 等 - 2013 - Understanding CeO2 as a Deacon catalyst by probe m DOI: 10.1039/C2CP42767B -
confidence 0.7
“Context: 'CO stretching region, at low coverages a signal centred at ... cm-1, 2155 arose' and 'C=O bond of the urea group'”
Erigoni 等 - 2019 - Acid properties of organosiliceous hybrid material DOI: 10.1039/C9CY01609K.
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