What absorbs at 1715 cm⁻¹ in an FTIR spectrum?
A band near 1715 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 1715 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 |
|---|---|---|---|
| Carbonyl (C=O) | 64 | 56 | 1.0 |
| Carboxyl (COOH) | 44 | 41 | 1.0 |
| Ester | 39 | 37 | 1.0 |
| Methacrylate | 38 | 36 | 1.0 |
| Acetate | 37 | 35 | 1.0 |
| Ketone | 35 | 33 | 1.0 |
| Amide | 35 | 33 | 1.0 |
| Alkene (C=C) | 8 | 8 | 1.0 |
| Alkyl C-H | 7 | 6 | 1.0 |
| C-O single bond | 5 | 5 | 1.0 |
| Methoxy (OCH3) | 4 | 4 | 1.0 |
| Aldehyde (CHO) | 3 | 3 | 1.0 |
| N h | 3 | 2 | 1.0 |
| Imide | 3 | 1 | 1.0 |
| Quinone | 2 | 2 | 1.0 |
| Carbohydrate | 2 | 2 | 1.0 |
| C=n | 1 | 1 | 1.0 |
| Metal oxygen | 1 | 1 | 1.0 |
| Water (H2O) | 1 | 1 | 1.0 |
| Hydroxyl (O-H) | 1 | 1 | 1.0 |
| Hydrogen bond | 1 | 1 | 0.8 |
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 |
|---|---|---|---|
| PET | 1715, 1408, 800 | Methacrylate, Carbonyl (C=O) | 1 |
| water | 1715, 1018, 2945 | Carbonyl (C=O), Methacrylate | 1 |
| glycerol | 1715, 1585, 1630 | Methacrylate, Carbonyl (C=O), Carboxyl (COOH) | 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 1715 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
“2, it is possible to observe an intense band in cm-1 the region of 1715 associated with the cis double bonds.”
Ariza Ortega 等 - 2012 - Analysis of trans fatty acids production and squal DOI: 10.2478/s11532-012-0104-4 -
Ester confidence 1.0
“are assigned to ester pectin polymer chains and the methyl group of the methyl ester The bands at 1715 and 1632 -COO(cid:0) CO-CH3”
Optimization of citron peel pectin and glycerol concentration in the production of edible film using response surface methodology DOI: 10.1016/j.heliyon.2023.e13724 -
Carbonyl (C=O) confidence 1.0
“At peak ~1715 cm-1, stretching of C=O bond were appeared indicated the conjugated ester group in the chemical”
Aziz 等 - 2018 - The effect of Pineapple Leaf Fiber (PALF) incorpor DOI: 10.1088/1755-1315/105/1/012082 -
Carbonyl (C=O) confidence 1.0
“cm-1 blends.21 the 1715 peak, corresponding to the carbonyl tration and DC in dimethacrylate C=O bond, showed reliable results.”
Collares 等 - 2014 - Discrepancies in degree of conversion measurements DOI: 10.1590/S1806-83242013000600002 -
Acetate confidence 1.0
“At wavenumber 1715.25 shows the presence of vibration C=O stretching and this oC, absorption band does not appear in the annealed sample 700 this is because the bond is broken due cm-1 to increasing temperatures.”
Fabiani 等 - 2020 - Green synthesis and characterization of Zinc Ferri DOI: 10.1088/1755-1315/599/1/012066 -
Ester confidence 1.0
“methylundecenoatesinceaslightsurfaceoxidationispresent:a 1715cm-1 2200cm-1, On this basis the band at can be univocally band at due to O ySi-H stretching vibration, and a x O ester stretching and the low frequency can assigned to the C sign”
Giovannozzi 和 Rocchia - 2008 - Effect of the reaction time, reagent concentration DOI: 10.1016/j.snb.2007.10.043 -
Acetate confidence 1.0
“The peaks at 1675cm-1 1715 and belong to the C O stretching bands of”
Iwai 等 - 2006 - Measurement of entrainer effects of water and etha DOI: 10.1016/j.supflu.2005.12.005 -
Acetate confidence 1.0
“The as-burnt and calcined 2 cm-1 BCZT powders with pH7 showed peaks at 1715, 1741, 1710 and 1742 assigned to the ACCEPTED MANUSCRIPT cm-1 C=O stretching [13].”
Influence of pH values on the surface and properties of BCZT nanopowders synthesized via sol-gel auto-combustion method DOI: 10.1016/j.surfcoat.2016.03.091
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