What absorbs at 3259 cm⁻¹ in an FTIR spectrum?
A band near 3259 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 5 cited sources
Quick answer
A band near 3259 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.
Возможные назначения функциональных групп
| Функциональная группа | Подтверждающие факты | Цитируемые источники | Максимальная достоверность |
|---|---|---|---|
| Hydroxyl (O-H) | 3 | 3 | 1,0 |
| N n bond | 1 | 1 | 1,0 |
| Ketone | 1 | 1 | 1,0 |
| Ester | 1 | 1 | 1,0 |
| Carboxyl (COOH) | 1 | 1 | 1,0 |
| Carbonyl (C=O) | 1 | 1 | 1,0 |
| Amide | 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 |
Ранжирование отражает накопленные литературные данные, а не единственное авторитетное правило. Всегда проверяйте в контексте вашего образца.
Possible materials
| Материал | Поддерживающие пики | Overlapping groups | Цитируемые источники |
|---|---|---|---|
| starch | 3259, 1650, 1540 | Hydroxyl (O-H) | 1 |
| glycerol | 3259, 1585, 1630 | Hydroxyl (O-H) | 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 3259 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.
Литература, лежащая в основе этих назначений
-
Hydroxyl (O-H) достоверность 1,0
“The peaks between 3259 and 3378 are represented to = Pb(1(cid:0) exp[(cid:0) kt]) M (8) O-H The strength of the stretching vibration band decreased much more than it did for SDB and OSDB and shifted somewhat to the lower where M (L/g VS add”
Enhancement of biogas production from individually or co-digested green algae Cheatomorpha linum using ultrasound and ozonation treated biochar DOI: 10.1016/j.ultsonch.2022.106197 -
Acetate достоверность 1,0
“substitution glyceraldehyde, L (-)-glucose 1727.10, 1645.08, 1158.41, OH bond scissoring, molecule 930.01, 1080.61, 861.22, 765.60 skeletal stretch, C=O, C-O stretch b-cyclodextrin OH, C=O stretch, OH bend, Water Native 3259.42, 2930.03, 20”
Influence of physical and chemical modifications on granule size frequency distribution, fourier transform infrared (FTIR) spectra and adsorption isotherms of starch from four yam (Dioscorea spp.) cultivars DOI: 10.1007/s13197-021-05200-7 -
N n bond достоверность 1,0
“LLM confirmed rule peak-group candidate”
Ren 等 - 2018 - Inhibition mechanism of Ca2+, Mg2+ and Fe3+ in fin DOI: 10.1098/rsos.180158 -
Hydroxyl (O-H) достоверность 1,0
“VibrationalModes Pure PVA Vibrational Modes PVA:CS Vibrational Modes Pure CS O-H stretching 3259.34 O-H stretching 3261.67 O-H stretching”
Development of Flexible Plasticized Ion Conducting Polymer Blend Electrolytes Based on Polyvinyl Alcohol (PVA): Chitosan (CS) with High Ion Transport Parameters Close to Gel Based Electrolytes DOI: 10.3390/gels -
достоверность 0,6
“Peak shifted from 3259 cm-1, attributed to glycerol presence.”
Synthesis of a novel monofilament bioabsorbable suture for biomedical applications DOI: 10.1002/jbm.b.35069
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