What absorbs at 3008 cm⁻¹ in an FTIR spectrum?
A band near 3008 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
Quick answer
A band near 3008 cm⁻¹ is usually interpreted by checking which functional groups repeatedly co-occur there in the literature, then confirming at least one or two additional peaks in the same sample. This page ranks those assignments by accumulated evidence rather than by a single fixed textbook rule.
Possible functional-group assignments
| Functional group | Supporting facts | Cited sources | Top confidence |
|---|---|---|---|
| Alkyl C-H | 19 | 18 | 1.0 |
| Alkene (C=C) | 14 | 13 | 1.0 |
| Fatty acid | 4 | 4 | 1.0 |
| Hydrogen bond | 3 | 3 | 1.0 |
| Hydroxyl (O-H) | 2 | 2 | 1.0 |
| Lipid | 1 | 1 | 1.0 |
| Methyl | 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 |
| C c single bond | 1 | 1 | 1.0 |
Ranking reflects accumulated literature evidence, not a single fixed rule. Always confirm against your sample context.
Possible materials
Materials are shown only when the same literature pool supports this band and at least one additional characteristic peak.
Spectrum logic
This band becomes meaningful only when read with its neighboring peaks. In practice, analysts first look at the assignments above, then check whether the same sample also shows other peaks expected for the same structural motif. A lone band near 3008 cm⁻¹ is usually not enough for material identification by itself.
Real-world usage
This type of query is common in polymer identification, unknown plastic screening, QC troubleshooting, recycled-material verification, and literature-backed peak assignment review.
Common mistakes
- Treating one isolated band as proof of a material without checking at least one or two supporting peaks.
- Ignoring overlap: multiple functional groups can contribute near the same wavenumber.
- Skipping validation when additives, blends, oxidation, or contamination may distort the spectrum.
Verification advice
When ambiguity remains, validate the hypothesis with DSC, GC-MS, or TGA, especially for blends, degraded samples, and filled polymers.
Literature behind these assignments
-
Alkene (C=C) confidence 1.0
“The vibration 3008 is assigned to =C-H”
Fourier transform infrared microspectroscopy detects biochemical changes during C. elegans lifespan DOI: 10.1016/j.vibspec.2019.04.005 -
Alkyl C-H confidence 1.0
“The band between (AAPF 2925.08 AAPP: cm-1) 3007.99 absorption was characterized as the C H stretch-”
Characterization of Auricularia auricula polysaccharides and its antioxidant properties in fresh and pickled product DOI: 10.1016/j.ijbiomac.2015.08.020 -
Alkyl C-H confidence 1.0
“The band at is due to the bending vibration of the C-H bonds 3008cm-1”
Naik 等 - 2019 - Optical and Electrical Properties of TCNQ Doped PM DOI: 10.1063/1.5100466 -
Fatty acid confidence 1.0
“In addition, the hydrocarbon chain in the synthesized compound which was formed from unsaturated fatty acid exhibited absorption peaks at ν of 3008.25”
Rahayu 等 - 2021 - Synthesis of oleic-imidazoline and investigation o DOI: 10.17675/2305-6894-2021-10-3-25 -
Alkene (C=C) confidence 1.0
“The 3008 peak is associated with cis-olefinic AV Oil PV b* L* a* BI cm(cid:0)”
Impact of microwave roasting on physicochemical properties, maillard reaction products, antioxidant activity and oxidative stability of nigella seed (Nigella sativa L.) oil DOI: 10.1016/j.foodchem.2021.130777 -
Hydrogen bond confidence 1.0
“The peaks observed at 3008, 2929 and 2854 represents the region of hydrogen bond stretching of the functional groups, peaks detected at cm-1 1745 and 1651 are attributed to the region of double bonds stretching of functional”
Impact of infrared and dry air roasting on the oxidative stability, fatty acid composition, Maillard reaction products and other chemical properties of black cumin (Nigella sativa L.) seed oil DOI: 10.1016/j.foodchem.2019.05.140 -
Hydroxyl (O-H) confidence 1.0
“cm-1 cm-1 cm-1) of peaks at 3008 and ~ 1740 in sub-fossil spectra represents phenol C-O/C-H bonds (1,150 became stronger.”
Influence of common palynological extraction treatments on ultraviolet absorbing compounds (UACs) in sub-fossil pollen and spores observed in FTIR spectra DOI: 10.3389/fevo.2023.1096099 -
Alkene (C=C) confidence 1.0
“There is a weak peak at 3008 time point and different temperature groups after death, we selected the caused by asymmetric cm(cid:0) cm(cid:0) 1 1 (=C-H).”
Adipose tissue estimates the postmortem interval based on ATR-FTIR spectroscopy DOI: 10.1016/j.microc.2021.105977
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 literature-backed analysis — in seconds.