What absorbs at 3447 cm⁻¹ in an FTIR spectrum?
A band near 3447 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 3447 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) | 9 | 8 | 1.0 |
| N h | 5 | 5 | 1.0 |
| Water (H2O) | 2 | 2 | 1.0 |
| Hydrogen bond | 2 | 2 | 1.0 |
| Alkyl C-H | 2 | 2 | 1.0 |
| Amine primary | 2 | 2 | 1.0 |
| Silicon (Si) | 2 | 2 | 1.0 |
| Silanol (Si-OH) | 1 | 1 | 1.0 |
| Methoxy (OCH3) | 1 | 1 | 1.0 |
| Methacrylate | 1 | 1 | 1.0 |
| C-O single bond | 1 | 1 | 1.0 |
| Acetate | 1 | 1 | 1.0 |
| Silicon-oxygen (Si-O) | 1 | 1 | 1.0 |
| Metal oxygen | 1 | 1 | 1.0 |
| Secondary amine | 1 | 1 | 1.0 |
| Carboxyl (COOH) | 1 | 1 | 0.9 |
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 |
|---|---|---|---|
| chitosan | 3447, 1650, 1655 | Hydroxyl (O-H), N h | 1 |
| silica | 3447, 1100, 1080 | Hydroxyl (O-H) | 1 |
| ZnO | 3447, 1400, 3430 | Hydroxyl (O-H) | 1 |
| NaOH | 3447, 3429, 897 | Hydroxyl (O-H) | 1 |
| AgNPs | 3447, 1232, 1048 | N h, Hydroxyl (O-H) | 1 |
| graphene | 3447, 1720, 2097 | Hydroxyl (O-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 3447 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
“7 shows a broad peak at 3446.91 corresponding to the stretching vibration of O H bonds.”
Production of graphene powder by electrochemical exfoliation of graphite electrodes immersed in aqueous solution DOI: 10.1016/j.ijleo.2016.04.101 -
Silicon (Si) confidence 1.0
“Alternatively, dehydroxylated silica can react with NH to 3 also explain why the corresponding broadband feature at form OH groups together with Si-NH 2, with corresponding cm(cid:4)1 cm(cid:4)1 (cid:2)2840 symmetric and asymmetric vibratio”
Leewis 等 - 2006 - Ammonia adsorption and decomposition on silica sup DOI: 10.1016/j.apsusc.2005.12.115 -
N h confidence 1.0
“The error bars were n T-shaped dimer has two NH stretching vibrations at 3447 and estimated from three data sets for each experimental condition.”
Matsumoto 和 Honma - 2007 - NH stretching vibrations of pyrrole clusters studi DOI: 10.1063/1.2790894 -
Hydroxyl (O-H) confidence 1.0
“The broad band at 3447 cm-1 corresponded to the O-H mode of vibration within the hydroxyl groups.”
Pauzi 等 - 2019 - Microwave-assisted Synthesis of ZnO Nanoparticles DOI: 10.9767/bcrec.14.1.3320.182-188) -
Hydroxyl (O-H) confidence 1.0
“The broad band at 3447 corresponded to the O-H mode of vibration within”
Gum Arabic As Natural Stabilizing Agent In Green Synthesis Of ZnO Nanofluids For Antibacterial Application DOI: 10.1016/j.jece.2019.103331 -
Hydroxyl (O-H) confidence 1.0
“As shown in Figure 2, the broad peak three times with sterile 1% PBS, and dried at room cm-1 centered around 3447 represent O-H stretching temperature for 30 min.”
Samantaray 等 - 2021 - Biosynthesized Silver Nanoparticles (AgNPs) from T DOI: 10.5530/ijper.55.3.153 -
confidence 1.0
“The peaks at 1000 and at geopolymers as follows 1000, 1432, 1639, and 3447 cm-1 1432 are attributed to asymmetric stretching vibrations of Al-O/Si-O bonds.”
Siyal 等 - 2014 - Effect of NaOH and Water Contents on Solidificatio DOI: 10.4028/www.scientific.net/AMM.625.3 -
confidence 1.0
“The peak at 3447 overlaps with N H stretching whose functional group is amine with a medium intensity.”
Chitin and Chitosan preparation from shrimp shells Penaeus monodon and its human Ovarian Cancer Cell Line, PA-1 DOI: 10.1016/j.ijbiomac.2017.09.035
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