What absorbs at 2852 cm⁻¹ in an FTIR spectrum?
A band near 2852 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 2852 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 | 65 | 62 | 1.0 |
| Methyl | 13 | 12 | 1.0 |
| Methacrylate | 9 | 9 | 1.0 |
| Acetate | 9 | 9 | 1.0 |
| Methoxy (OCH3) | 8 | 8 | 1.0 |
| Lipid | 6 | 6 | 1.0 |
| Hydroxyl (O-H) | 3 | 3 | 1.0 |
| Alkene (C=C) | 3 | 3 | 1.0 |
| Amide | 3 | 2 | 1.0 |
| Carbonyl (C=O) | 2 | 2 | 1.0 |
| Protein alpha helix | 2 | 2 | 1.0 |
| Ester | 2 | 2 | 1.0 |
| Carboxyl (COOH) | 2 | 2 | 1.0 |
| Hydrogen bond | 1 | 1 | 1.0 |
| Ketone | 1 | 1 | 1.0 |
| Aromatic ring | 1 | 1 | 1.0 |
| Amine primary | 1 | 1 | 1.0 |
| N h | 1 | 1 | 1.0 |
| Carbohydrate | 1 | 1 | 1.0 |
| N-O bond | 1 | 1 | 1.0 |
Ranking reflects accumulated literature evidence, not a single fixed rule. Always confirm against your sample context.
Possible materials
| Material | Supporting peaks | Overlapping groups | Cited sources |
|---|---|---|---|
| cellulose nanocrystals | 2852, 1110, 1640 | Acetate, Methacrylate, Alkyl C-H | 1 |
| DNA | 2852, 1712, 1660 | Methacrylate, Acetate | 1 |
| cells | 2852, 970, 1741 | Alkyl C-H, Methacrylate, Acetate | 1 |
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 2852 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
-
Alkyl C-H confidence 1.0
“LLM confirmed rule peak-group candidate”
Isolation and Characterization of Cellulose Nanocrystals from Oil Palm Mesocarp Fiber DOI: 10.3390/polym9080355 -
Alkyl C-H confidence 1.0
“Two other major peaks C-H symmetric stretching (aliphatic) peak was noted at 2852.25 cm(cid:3)1, which are related to C-H bending in CH and CH 3, were observed at 1458.91 and 1376.47”
Effect of used motor oil as a rejuvenator on crumb rubber modifier’s released components to asphalt binder DOI: 10.1177/1477760620918600 -
Alkyl C-H confidence 1.0
“In the NaOl spectrum, the peak at 1470 is attributed to -CH 2 cm-1 bending while the peaks at 2852, 2921, 2955, and 3005 are ascribed to the symmetric stretching vibrations of -CH 2, asymmetric stretching of -CH 2, asymmetric stretching of”
Adsorption mechanisms of fatty acids on fluorite unraveled by infrared spectroscopy and first-principles calculations DOI: 10.1016/j.jcis.2020.09.062 -
Alkyl C-H confidence 1.0
“LLM confirmed rule peak-group candidate”
Kim 等 - 2015 - Controlled growth of CdSe quantum dots on silica s DOI: 10.1117/12.2187697 -
Alkyl C-H confidence 1.0
“These results identified cm-1 and the absorption peak at 2852 can be attributed to alkyl, phenolic hydroxyl, and carboxyl functional groups in the stretching vibrations of carbon hydrogen bonds (C-H) or the extract of black point diseased k”
Enzymatic Browning in Wheat Kernels Produces Symptom of Black Point Caused by Bipolaris sorokiniana DOI: 10.3389/fmicb.2020.526266 -
Alkyl C-H confidence 1.0
“2006)and information about the acylchainsin general.Theresults 970cm-1 2852cm-1, A decrease in absorbance of the show that the amplitude of CH band was attributed symmetric stretching at 2 2925cm-1, (C-C to changes in the deoxyribose-phosph”
A new approach to studying the effects of ionising radiation on single cells using FTIR synchrotron microspectroscopy DOI: 10.1016/j.radphyschem.2013.03.037 -
Alkyl C-H confidence 1.0
“g2D-COR,whereasaminutechangewasobservedat2852cm-1.Thisis are related to the symmetric and asymmetric stretching vibration of the aliphatic -CH2bonds.”
Getting inside on virgin olive oil (VOO) photooxidation kinetics through combined generalized 2D correlation analysis and moving window 2D correlation analysis of ATR-FTIR spectra DOI: 10.1016/j.talanta.2020.120917 -
Alkyl C-H confidence 1.0
“Explicit assignment: '2852-2855 cm-1' as CH stretching”
Shi 等 - 2018 - Biochemical alterations of Candida albicans during DOI: 10.1039/c8an01452c
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