What absorbs at 3243 cm⁻¹ in an FTIR spectrum?
A band near 3243 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 3243 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.
Atribuiri posibile ale grupelor funcționale
| Grup funcțional | Fapte suport | Surse citate | Încredere maximă |
|---|---|---|---|
| N h | 3 | 3 | 1,0 |
| Hydroxyl (O-H) | 2 | 2 | 1,0 |
| Secondary amine | 1 | 1 | 1,0 |
| Water (H2O) | 1 | 1 | 1,0 |
| Alkyl C-H | 1 | 1 | 1,0 |
Clasamentul reflectă dovezile acumulate din literatură, nu o singură regulă autoritară. Confirmați întotdeauna în contextul mostrei dvs.
Possible materials
| Material | Vârfuri suport | Overlapping groups | Surse citate |
|---|---|---|---|
| hydrogel | 3243, 1632, 1062 | Hydroxyl (O-H), N 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 3243 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.
Literatura din spatele acestor atribuiri
-
Hydroxyl (O-H) încredere 1,0
“LLM confirmed rule peak-group candidate”
Synthesis, Structural, Optical, Electrical and Thermal Studies of Poly(vinyl alcohol)/CdO Nanocomposite Films DOI: 10.1007/s10904-017-0662-1 -
încredere 1,0
“The maximum at 3243 cm-1 which corresponds to symmetric valence vibrations of N-H bonds from the sulfonamide NH2 group was shifted for 25 units in relation to its position in the sulfanilamide spectrum (3268 cm-1).”
Modified Sulfanilamide Release from Intelligent Poly(N-isopropylacrylamide) Hydrogels DOI: 10.3390/pharmaceutics15061749 -
Hydroxyl (O-H) încredere 1,0
“Phenols, a group of 3243cm-1 range of is ascribed to stretching vibrations bioactive compounds that define the therapeutic value of of hydroxyl group of water molecules (Muzaffar et al., plants, are known to absorb frequencies in the range”
Qadri 等 - 2022 - Comparative evaluation of apple juice concentrate DOI: 10.15586/qas.v14i2.1037 -
N h încredere 1,0
“220(cid:3)C 223(cid:3)C, Off white solid, Yield: 86%, m.p: to Rf: 0.65 (C6), 148.4 (C14), 134.7 (C12), 130.6 (C15), 130.0 (C16), cm-1): n-hexane [Acetone: (7:3)], FTIR (KBr disk, 122.2 (C17, C19), 121.2 (C10), 111.9 (C9), 109.3 (C8), [M]+,”
Development of an Efficient, One-Pot, Multicomponent Protocol for Synthesis of 8-Hydroxy-4-Phenyl-1,2-Dihydroquinoline Derivatives DOI: 10.1002/jhet.4193 -
N h încredere 0,9
“N-H vibration mode”
Kurmanbayeva 等 - 2020 - Tetrapropylammonium Hydroxide as a Zinc Dendrite G DOI: 10.3389/fenrg.2020.599009
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