What absorbs at 3210 cm⁻¹ in an FTIR spectrum?

Quick answer

A band near 3210 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.

可能性のある官能基アサイン

ランキングは蓄積された文献証拠を反映しており、単一の権威あるルールではありません。常にサンプルのコンテキストと照合して確認してください。

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 3210 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.

これらのアサインの根拠となる文献

• 信頼度 1.0

  “The primary N-H bonds peaking at 3210”

  Miyazaki 等 - 2005 - Properties of radio-frequency-sputter-deposited Ga DOI: 10.1063/1.1888027g
• Hydroxyl (O-H) 信頼度 1.0

  “The absorption at ~3210 assigned to wagging vibrations hydrogen-bonded hydroxyl group vibrations (poly -OH1).”

  Influences of Ash-Existing Environments and Coal Structures on CO2 Gasification Characteristics of Tri-High Coal DOI: 10.3390/pr8111367
• Water (H2O) 信頼度 1.0

  “However, after eight months (Figure 5b), the mixtures with 5 and 10% of water showed new peaks (3346 and 3208 cm-1, and 3344 and 3210 cm-1, respectively) in the OH region, probably due to the crystallization Molecules2022,27,8310”

  Elaboration and Characterization of Natural Deep Eutectic Solvents (NADESs): Application in the Extraction of Phenolic Compounds from pitaya DOI: 10.3390/molecules27238310
• 信頼度 1.0

  “Spectral Characteristics of Inorganic Ions in Aerosols PM N-H bond absorbance bands at approximately 3210 and samples were collected on filters, then analyzed”

  Wei 等 - 2019 - Aerosol Pollution Characterization before Chinese DOI: 10.4209/aaqr.2018.06.0226
• Hydroxyl (O-H) 信頼度 1.0

  “height in horizontal/vertical direction of the infrared polar3210, and 3060 These bands are ascribed to intrinsic izer, indicating that this material is homogenous in both its OH in aluminous orthopyroxene (Beran and Zemann 1986;”

  Water contents of nominally anhydrous orthopyroxenes from oceanic peridotites determined by SIMS and FTIR DOI: 10.1007/s00710-021-00757-9
• 信頼度 1.0

  “Compared with the spectra of the reaction monomers MAA and DOPA, in the FTIR spectra of L-DMA, the absorption peaks of methacrylic anhydride in MAA at 1787 and cm-1 cm-1, 1725 had obviously disappeared and changed into a single peak of C=O”

  Bionic Synthesis of Mussel-like Adhesive L-DMA and Its Effects on Asphalt Properties DOI: 10.3390/ma15155351