What absorbs at 2015 cm⁻¹ in an FTIR spectrum?
A band near 2015 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 2015 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 |
|---|---|---|---|
| Amide | 5 | 5 | 1.0 |
| N h | 4 | 4 | 1.0 |
| Methacrylate | 4 | 4 | 1.0 |
| Acetate | 4 | 4 | 1.0 |
| Methoxy (OCH3) | 3 | 3 | 1.0 |
| C-O single bond | 3 | 3 | 1.0 |
| Carbonyl (C=O) | 2 | 2 | 1.0 |
| Alkyl C-H | 2 | 2 | 1.0 |
| Secondary amine | 1 | 1 | 1.0 |
| Aromatic ring | 1 | 1 | 1.0 |
| Ketone | 1 | 1 | 1.0 |
| Ester | 1 | 1 | 1.0 |
| Carboxyl (COOH) | 1 | 1 | 1.0 |
| C c single bond | 1 | 1 | 1.0 |
| Fatty acid | 1 | 1 | 1.0 |
Ranking reflects accumulated literature evidence, not a single authoritative rule. Always confirm against your sample context.
Possible materials
| Material | Supporting peaks | Overlapping groups | Cited sources |
|---|---|---|---|
| PVA | 2015, 1660, 2930 | Acetate, Methacrylate, Amide | 1 |
| chitosan | 2015, 1650, 1655 | Amide, Acetate, Methacrylate | 1 |
| collagen | 2015, 1408, 1660 | Amide, 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 2015 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
-
Acetate confidence 1.0
“Earlier 3 band of free amino acids.A broad band with the maxima at around 1698 researchers reported that the amorphous materials are unstable if stored - 1 and 1636 cm related to the bending vibrations of -OH from water at temperature close”
Exploiting maltodextrin and whey protein isolate macromolecules as carriers for the development of freeze dried honey powder DOI: 10.1016/j.carpta.2021.100040 -
Alkyl C-H confidence 1.0
“C‚O C‚C CAO stretch or stretch, CH bend, stretch and 2015;”
Ge 等 - 2017 - Characteristics of activated carbon remove sulfur DOI: 10.1016/j.sjbs.2016.12.016 -
Amide confidence 1.0
“When comparing the neat collagen membranes and those coated with chitosan and crosslinked with glutaraldehyde, the amide absorption bands Materials2015,8,7673-7689”
Chitosan-Coated Collagen Membranes Promote Chondrocyte Adhesion, Growth, and Interleukin-6 Secretion DOI: 10.3390/ma8115413 -
Amide confidence 1.0
“The FTIR result may strongly suggests that BLGu BSG mixed system is a typical thermodynamic incompatible as amide I peak was increased in n 2015 the BLG-BSG mixed system comparing with the BLG, BSG in solution and gel states.”
Rafe 和 Razavi - 2015 - Effect of Thermal Treatment on Chemical Structure DOI: 10.1080/10942912.2014.999864 -
confidence 1.0
“II IR for the aluminium surfaces" peak assignments 2015 January 05 based on refs [11, 12].”
STRALIN 和 HJERTBERG - 1992 - A FTIR STUDY OF INTERFACIAL INTERACTIONS BETWEEN E DOI: 10.1163/156856192X00584 -
C c single bond confidence 1.0
“This peak is Materials 2015, 8 4905 related to the symmetric C-C stretching mode or stretching of the C-O of a portion of the chain where an intramolecular hydrogen bond is formed between two neighboring -OH groups that are on the same”
Poly(vinyl alcohol) Nanocomposites Reinforced with Bamboo Charcoal Nanoparticles: Mineralization Behavior and Characterization DOI: 10.3390/ma8084895 -
confidence 1.0
“Biomass to the C = O stretching from the amide group while the peak cm-1 The mushroom chitosan-harvested biomass has EPA levels up at 1600 is the amine peak (Dimzon and Knepper, 2015).”
Effective Harvesting of Nannochloropsis Microalgae Using Mushroom Chitosan: A Pilot-Scale Study DOI: 10.3389/fbioe.2020.00771 -
Acetate confidence 1.0
“It can be seen that, within a corresponds to C=O amide stretching from proteins, which is circledcluster, inmostcases, theT7samples lietotheleftrelativeto alsocalledtheamideIband(CeylanandGoldfarb,2015).Forlater theT14samples.Frombottomtoto”
ATR-FTIR spectroscopy combined with multivariate analysis as a rapid tool to infer the biochemical composition of Ulva laetevirens (Chlorophyta) DOI: 10.3389/fmars.2023.1154461
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 confidence-rated evidence chain — in seconds.