What absorbs at 3391 cm⁻¹ in an FTIR spectrum?

Quick answer

A band near 3391 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.

가능한 작용기 할당

순위는 단일 권위 규칙이 아닌 축적된 문헌 증거를 반영합니다. 항상 샘플 상황에 대해 확인하세요.

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 3391 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.

이 할당의 배경이 되는 문헌

• Hydroxyl (O-H) 신뢰도 1.0

  “2 cm-1, cm-1 SnO nanoparticles show transmittance peaks at 3391 and 1568 which are associated to the 2 cm-1, vibration of stretching OH, while peaks at a wave number of 625, 930, and 1635 indicating the appearance of the stretching mode of”

  Diantoro 等 - 2018 - Control of Dielectric Constant and Anti-Bacterial DOI: 10.1088/1757-899X/367/1/012012
• Carboxyl (COOH) 신뢰도 1.0

  “(6 h without toluene), which displayed a hydroxyl peak absorption, but without the unsaturation removal, and the synthetic reaction with formic acid that presented a peak elongation in the hydroxyl (3391 cm-1) and unsaturation loss (3009 cm”

  Montenegro 等 - 2023 - Enzymatic and Synthetic Routes of Castor Oil Epoxi DOI: 10.3390/polym15112477
• N h 신뢰도 1.0

  “1200 900 These peaks are assigned cm-1, Polypyrrole exhibit characteristic peaks at 3391 to NH stretching vibration (ν-NH 2), CH stretching cm-1, cm-1, cm-1, cm-1, cm-1 1536 1444 1297 1041 784”

  Moosvi 等 - 2016 - Studying the electrical, thermal, and photocatalyt DOI: 10.1590/1980-5373-MR-2015-0786
• Hydroxyl (O-H) 신뢰도 1.0

  “3300-3400 -OH stretch ± ± 3391 26.1 0.3 3266 9.3 0.1 ± ± 2920 12.8 0.1 2921 9.1 0.1 -CH 2asymmetric stretch”

  Grape Canes (Vitis vinifera L.) Applications on Packaging and Particleboard Industry: New Bioadhesive Based on Grape Extracts and Citric Acid DOI: 10.3390/polym14061137
• Hydroxyl (O-H) 신뢰도 0.9

  “Peak at 3391 cm-1 corresponds to -OH stretch.”

  Arla 等 - 2018 - CHARACTERIZATION AND QUANTIFICATION OF ETHYLHEXYLG DOI: 10.13040/IJPSR.0975-8232.9(4).1660-65
• Hydroxyl (O-H) 신뢰도 0.8

  “Absorption at 3391 cm-1 attributed to OH groups.”

  Li 等 - 2020 - Solvent-free synthesis of 1-amidoalkyl-2-naphthol DOI: 10.2478/pjct-2020-0012