What absorbs at 2951 cm⁻¹ in an FTIR spectrum?
A band near 2951 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 7 cited sources
Possible functional-group assignments
| Functional group | Supporting facts | Cited sources | Top confidence |
|---|---|---|---|
| Alkyl C-H | 4 | 3 | 1.0 |
| Methyl | 1 | 1 | 1.0 |
| Methoxy (OCH3) | 1 | 1 | 0.9 |
Ranking reflects accumulated literature evidence, not a single authoritative rule. Always confirm against your sample context.
Literature behind these assignments
-
Methyl confidence 1.0
“Explicit assignment in text”
Pusnik Cresnar 等 - 2020 - Effect of Wood Fiber Loading on the Chemical and T DOI: 10.3390/app10248863 -
Alkyl C-H confidence 0.95
“explicit assignment”
Gorniak 等 - 2022 - Preformulation Studies of Ezetimibe-Simvastatin So DOI: 10.3390/pharmaceutics14050912 -
Alkyl C-H confidence 0.95
“explicit assignment for SIM”
Gorniak 等 - 2023 - Screening of Fenofibrate-Simvastatin Solid Dispers DOI: 10.3390/pharmaceutics15020603 -
confidence 0.9
“Explicit assignment in text.”
Bhatia 等 - 2023 - The Effect of Sage (Salvia sclarea) Essential Oil DOI: 10.3390/gels9030233 -
confidence 0.9
“Text: 'peak at 2951 is associated with -CH3 bonds'.”
Saleema 等 - 2012 - Polymer Masks Fabrication by Micropatterning Surfa DOI: 10.1163/156856111X623113 -
Alkyl C-H confidence 0.9
“Assigned to CH asymmetric stretching of PMMA.”
Shanmugasundar 等 - 2019 - Study on the inflammatory response of PMMApolysty DOI: 10.1371/journal.pone.0209948 -
Methoxy (OCH3) confidence 0.9
“Explicit assignment in text.”
Shtyka 等 - 2020 - Photocatalytic Reduction of CO2 Over Me (Pt, Pd, N DOI: 10.1007/s11244-020-01241-y
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