What absorbs at 3387 cm⁻¹ in an FTIR spectrum?
A band near 3387 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 8 cited sources
Quick answer
A band near 3387 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
| Functional group | Supporting facts | Cited sources | Top confidence |
|---|---|---|---|
| Hydroxyl (O-H) | 7 | 6 | 1.0 |
| N h | 3 | 3 | 1.0 |
| Water (H2O) | 2 | 2 | 1.0 |
| Secondary amine | 1 | 1 | 1.0 |
| Amine primary | 1 | 1 | 1.0 |
Ranking reflects accumulated literature evidence, not a single fixed rule. Always confirm against your sample context.
Possible materials
| Material | Supporting peaks | Overlapping groups | Cited sources |
|---|---|---|---|
| TiO2 | 3387, 1700, 1093 | Hydroxyl (O-H) | 1 |
| TiO2 nanoparticles | 3387, 1700, 455 | 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 3387 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
-
Hydroxyl (O-H) confidence 1.0
“with poly(vinyl alcohol) with the O-H stretching of alcohol at 3387 The 177 cm-1 vibrational band at 2943 refers to the C-H stretching of alkyl groups, including 178”
Synthesis of lanthanum tungstate interconnecting nanoparticles by high voltage electrospinning DOI: 10.1016/j.apsusc.2015.05.194 -
Amine primary confidence 1.0
“cm-1 of primary amine, i.e., -NH and peak at 3387 is responsible P-cymene a triterpenoid was reported with RT of 5.124 min.”
Shareef 和 Bhavya - 2021 - Extraction, phytochemical analysis and in silico a DOI: 10.21276/ap.2021.10.2.59 -
Hydroxyl (O-H) confidence 1.0
“In PH-Et phospholipids extract the broad and 1607 correspond to stretching vibrations of carcm-1 cm-1 1600-1420 band centered at 3387 bonyl groups, the bands at represents the OH stretching, correspond cm-1 cm-1 cm-1 the principal bands at”
Aisha 等 - 2014 - Preparation and characterization of nano liposomes DOI: 10.1155/2011/103039. -
Hydroxyl (O-H) confidence 1.0
“The band at 3387 cm-1 are assigned to O-H stretching vibration bonds due to moisture adsorption on the material's surface [20,33].”
A Highly Selective Novel Green Cation Exchange Membrane Doped with Ceramic Nanotubes Material for Direct Methanol Fuel Cells DOI: 10.3390/en14185664 -
confidence 1.0
“Theophylline showed characteristic peaks of C=O stretching at 1716.7-1668.48, N-H stretching at 3387.113261.74, C=N stretching at 1568.69, C=C stretching at 1820.86 and C-N stretching at 1313.57cm-1.”
Meka 等 - 2016 - Design and statistical optimization of an efferves DOI: 10.1515/acph-2016-0002 -
Hydroxyl (O-H) confidence 1.0
“RSP/RM-β-CD The UATR-FTIR spectrum of inclusion complex exhibits a broad cm-1 cm-1) band between 3500 and 3300 (peak at 3387 related to hydroxyl groups (O-H stretching vibration) and other several bands noticed in Table 1;”
Sbarcea 等 - 2021 - RisperidoneRandomly Methylated beta-Cyclodextrin DOI: 10.3390/molecules26061690 -
confidence 1.0
“Peaks observed at 3387.15/cm correspond to N-H stretch (amines) and O-H stretch (alcohols);”
Usmani 等 - 2023 - Molecular Docking of Bacterial Protein Modulators DOI: 10.3390/molecules28020574 -
Water (H2O) confidence 1.0
“stretching stretching 3405 3387 stretching stretching vibration mode of lattice water vibration mode of lattice water 3387 3405”
Removal of Tetracycline by Hydrous Ferric Oxide: Adsorption Kinetics, Isotherms, and Mechanism DOI: 10.3390/ijerph16224580
Have a spectrum with this band?
Upload your FTIR spectrum and get a full interpretation report — peak assignments with literature citations, library matches, and a literature-backed analysis — in seconds.