What absorbs at 3339 cm⁻¹ in an FTIR spectrum?

Quick answer

A band near 3339 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

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 3339 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

• Carboxyl (COOH) confidence 1.0

  “cm-1, For Equia Forte, a marked peak was observed at 3339 corresponding to the Figure 4 shows the graphs corresponding to Ketac Molar for the different thicknesses cm-1, COO-, presence of OH groups, and a peak at 1636 corresponding to follo”

  Remineralization Potential of Three Restorative Glass Ionomer Cements: An In Vitro Study DOI: 10.3390/jcm12062434
• Hydroxyl (O-H) confidence 1.0

  “Another study confirmed the green synthesis of of an absorption band at 3339 which can be assigned to O-H stretching of phenolic cm-1 silver nanoparticles utilizing aqueous leaf extract of Aegle marmelos, with the formation of compounds [62”

  Facile Green Synthesis of Zinc Oxide Nanoparticles with Potential Synergistic Activity with Common Antifungal Agents against Multidrug-Resistant Candidal Strains DOI: 10.3390/cryst12060774
• Hydroxyl (O-H) confidence 1.0

  “The O-H stretching vibration is cm-1 responsible for a broad and intense absorption peak centered at 3339 [36].”

  Innovative Green Chemistry Approach to Synthesis of Sn2+-Metal Complex and Design of Polymer Composites with Small Optical Band Gaps DOI: 10.3390/molecules27061965
• confidence 1.0

  “As shown in Figure 8a,b, the peak near 3339 cm-1 is due to the N-H tensile vibration of the cm-1 As shown in Figure 8a,b, the peak near 3339 is due to the N-H tensile vibration of the”

  Mechanism and Improved Dissolution of Glycyrrhetinic Acid Solid Dispersion by Alkalizers DOI: 10.3390/pharmaceutics12010082
• N h confidence 1.0

  “In addition, an absorption peak related to C-N The BET surface area decreased in bentonite@Cl (238.627 Accepted cm-1 stretching vibrations of guanidine at 1615 and peak related m²/g) compared with bento-crt (24.032 m²/g) which may be 3339cm”

  Palladium Nanoparticles on a Creatine‐Modified Bentonite Support: An Efficient and Sustainable Catalyst for Nitroarene Reduction DOI: 10.1002/cplu.201900377
• confidence 1.0

  “The C=O absorption peak at 1749 and cm-1 N-H absorption peak at 3339 were observed in the neat PPC and TPU respectively.”

  Biodegradable and Toughened Composite of Poly(Propylene Carbonate)/Thermoplastic Polyurethane (PPC/TPU): Effect of Hydrogen Bonding DOI: 10.3390/ijms19072032
• Hydroxyl (O-H) confidence 1.0

  “The most two obvious absorption peaks at 3339 cm-1 and 1030 cm-1 are ascribed to the -OH stretching and C-O stretching, respectively.”

  Enhancing Insulating Performances of Presspaper by Introduction of Nanofibrillated Cellulose DOI: 10.3390/en10050681
• Hydroxyl (O-H) confidence 1.0

  “The occurrence of peaks between 3697 and 3444 the spectral region between 3755 and 2900 includes two cm-1 in the spectra of HA (Figure 3b) indicates the presence characteristic absorptions of humified material, 3339 and cm-1, of mineral imp”

  Merlin 等 - 2015 - Instrumental and Experimental Conditions for the A DOI: 10.5935/0103-5053.20150170