What absorbs at 2956 cm⁻¹ in an FTIR spectrum?
A band near 2956 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 8 cited sources
Possible functional-group assignments
| Functional group | Supporting facts | Cited sources | Top confidence |
|---|---|---|---|
| Alkyl C-H | 4 | 4 | 1.0 |
| Methyl | 3 | 2 | 0.9 |
| Hydroxyl (O-H) | 2 | 1 | 0.9 |
| Lipid | 1 | 1 | 0.7 |
Ranking reflects accumulated literature evidence, not a single authoritative rule. Always confirm against your sample context.
Literature behind these assignments
-
Alkyl C-H confidence 1.0
“Explicit assignment in text.”
Mansour 等 - 2017 - Elucidation of penetration enhancement mechanism o DOI: 10.1016/j.saa.2017.05.026 -
confidence 1.0
“Explicit assignment in text.”
Sulym 等 - 2019 - Superhydrophobic MWCNTsPDMS-nanocomposite materia DOI: 10.5277/ppmp19057 -
Alkyl C-H confidence 0.9
“Text: 'sp3 C-H stretch 2956.34'”
Chong 等 - 2016 - An improved method for aldol condensation catalyse DOI: 10.1515/gps-2015-0126 -
confidence 0.9
“Explicit assignment to thyme.”
Macchia 等 - 2022 - In-Situ Comparative Study of Eucalyptus, Basil, Cl DOI: 10.3390/mps5030037 -
Methyl confidence 0.9
“Text: 'The band at 2956 related to methyl'”
Markovic 等 - 2009 - THE EFFECT OF GAMMA RADIATION ON THE AGEING OF SUL DOI: 10.2298/CICEQ0904291M -
Methyl confidence 0.9
“Explicit assignment: '2956 due to ... methyl vibration'.”
Mazlan 和 Abu Hanifah - 2014 - Synthesis and Effect of Modification On Methacylat DOI: 10.1063/1.4895206 -
Alkyl C-H confidence 0.7
“Peak at 2956 cm-1 assigned to CH2 stretching (implied by context).”
Guleken 等 - 2022 - Diagnosis of endometriosis using endometrioma volu DOI: 10.1016/j.saa.2021.120246 -
Hydroxyl (O-H) confidence 0.7
“Presence of O-H vibration.”
Ponnusamy 等 - 2021 - A Parametric Study on a Diesel Engine Fuelled Usin DOI: 10.3390/su13137195
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