What absorbs at 1597 cm⁻¹ in an FTIR spectrum?
A band near 1597 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 1597 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 |
|---|---|---|---|
| Aromatic ring | 11 | 10 | 1.0 |
| Alkene (C=C) | 7 | 7 | 1.0 |
| N h | 6 | 6 | 1.0 |
| Ring structure | 6 | 5 | 1.0 |
| Carboxyl (COOH) | 4 | 4 | 1.0 |
| Secondary amine | 4 | 4 | 1.0 |
| Amide | 4 | 4 | 1.0 |
| Carbonyl (C=O) | 3 | 3 | 1.0 |
| C c single bond | 2 | 2 | 1.0 |
| Methacrylate | 2 | 2 | 1.0 |
| Acetate | 2 | 2 | 1.0 |
| C=n | 2 | 2 | 1.0 |
| Amine primary | 2 | 1 | 1.0 |
| Hydroxyl (O-H) | 1 | 1 | 1.0 |
| Alkyl C-H | 1 | 1 | 1.0 |
| Nitrogen heterocycle | 1 | 1 | 1.0 |
| Carbonate | 1 | 1 | 1.0 |
| Water (H2O) | 1 | 1 | 1.0 |
| Ketone | 1 | 1 | 1.0 |
| Ester | 1 | 1 | 1.0 |
| Lignin | 1 | 1 | 1.0 |
| S s | 1 | 1 | 1.0 |
| Methoxy (OCH3) | 1 | 1 | 1.0 |
| C-O 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 1597 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
-
Amide confidence 1.0
“In general, chitosan powder show characteristic peaks at 3425.58 cm-1 cm-1 cm-1 (-OH and -NH stretching), 2877.79 (-CH stretching), 1651.07 (amide I/C=O stretching), 2 cm-1 cm-1 cm-1 1597.06 (amide II/-NH bending), 1072.42 (C-O-C stretching”
Cahyono 等 - 2018 - Characteristics of eugenol loaded chitosan-tripoly DOI: 10.1088/1757-899X/349/1/012010 -
Acetate confidence 1.0
“The absorption band at 1324 is attributed to the bending C-O cm-1 stretching, and the strong peak at 1597 is vibration of the”
A composite chitosan derivative nanoparticle to stabilize a W1/O/W2 emulsion: Preparation and characterization DOI: 10.1016/j.carbpol.2020.117533 -
Carboxyl (COOH) confidence 1.0
“30 peaks at 3288.63 represents for alcoholic group, OH stretch, 2926.01 for carboxylic acid OH 31 32 Accepted stretch, 1597.06 for aliphatic nitro compounds, and 1379.10 for organic sulfates in the region of 33”
Kalpana 和 Rajeswari - 2018 - Synthesis of palladium nanoparticles via a green r DOI: 10.1088/2053-1591/aaddef -
C c single bond confidence 1.0
“2 (1560-1610cm-1) in size, shape and most likely in habit because all the characto aromatic C C stretching vibration is peaking 1597cm-1.”
Sharma 等 - 2009 - On the affinity of Chuaria-Tawuia complex A multi DOI: 10.1016/j.precamres.2009.04.003 -
Alkene (C=C) confidence 1.0
“The peak at 1597 in the spectra for tensile fatigue aging can be assigned to the stretching vibration absorption of the double bond of conjugated cm21 dienes, and the peaks at 1415 and 1015 can be assigned to the in-plane and out-of-plane b”
Effects of hot-air aging and dynamic fatigue on the structure and dynamic viscoelastic properties of unfilled natural rubber vulcanizates DOI: 10.1002/app.27216 -
S s confidence 1.0
“The bands at 1597 and beduetoC�O ground state S might stretchingvibrations,while thebandat to higher energy states S S S S etc.”
Ahmad 等 - 2021 - Spectroscopic Analysis for Harnessing the Quality DOI: 10.1155/2021/6629640 -
Aromatic ring confidence 1.0
“cm-1 Infrared spectrum of curcumin showed its signature peaks at 3508 (phenolic O-H stretching cm-1 cm-1 vibration), 1628 (aromatic moiety C=C stretching), 1597 (benzene ring stretching Bull.”
Ahmed 等 - 2021 - STRUCTURAL AND OPTICAL CHARACTERISTICS OF POLY(VIN DOI: 10.4314/bcse.v35i3.12 -
Carboxyl (COOH) confidence 1.0
“vibration bands were displaced to 1597 and 1425 Comparison of the -COO vibrations in the spectra showed displacements, especially for ʋ(-COO) sym”
Modified bacterial cellulose scaffolds for localized doxorubicin release in human colorectal HT-29 cells DOI: 10.1016/j.colsurfb.2016.01.007
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