What absorbs at 1344 cm⁻¹ in an FTIR spectrum?
A band near 1344 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 1344 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 |
|---|---|---|---|
| Methoxy (OCH3) | 4 | 4 | 1.0 |
| Methacrylate | 4 | 4 | 1.0 |
| C-O single bond | 4 | 4 | 1.0 |
| Acetate | 4 | 4 | 1.0 |
| Alkyl C-H | 3 | 3 | 1.0 |
| Hydroxyl (O-H) | 3 | 3 | 1.0 |
| Aromatic ring | 2 | 2 | 1.0 |
| Lipid | 1 | 1 | 1.0 |
| Amino acid | 1 | 1 | 1.0 |
| Nitro (NO2) | 1 | 1 | 1.0 |
| S s | 1 | 1 | 1.0 |
| N h | 1 | 1 | 1.0 |
| Amine primary | 1 | 1 | 1.0 |
| Hydrogen bond | 1 | 1 | 1.0 |
| Alkene (C=C) | 1 | 1 | 1.0 |
Ranking reflects accumulated literature evidence, not a single authoritative rule. Always confirm against your sample context.
Possible materials
| Material | Supporting peaks | Overlapping groups | Cited sources |
|---|---|---|---|
| diamond | 1344, 1378, 1332 | Methoxy (OCH3) | 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 1344 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
-
confidence 1.0
“Recorded in Fig.2(a), the incorporated nitrogen impurity in the form of single substitutional atoms (C-centers) is corresponding to the peaks at 1344cm-1, 1130 and which is attributed to typical Ib”
B–C Bond in Diamond Single Crystal Synthesized with h-BN Additive at High Pressure and High Temperature DOI: 10.1088/0256-307X/33/2/028101 -
confidence 1.0
“Characteristic absorption for C-centers (single substitutional N atoms).”
Li 等 - 2017 - Synthesis of n-type semiconductor diamond single c DOI: 10.1088/1757-899X/274/1/012131 -
Acetate confidence 1.0
“peaks located at 1147, 1344, and 1369 due to C-O stretching vibrationofesterandCH3bendingvibrationoflipid.Thepeaks 1344cm-1 around 1083, 1137, 1186, and are caused by C-O distinguished from the absorption.”
Wu 等 - 2023 - Infrared and Terahertz Spectra of Pu'er White Tea DOI: 10.1155/2023/3290917 -
confidence 1.0
“5 illustrates that nitrogen in diamond is predominantly in cm-1 at the C-form with strong and sharp peaks at 1130 and 1344 cm-1) low temperature (below 1500 °C).”
Yan 等 - 2016 - The effect of phosphorus and nitrogen co-doped on DOI: 10.1016/j.ijrmhm.2015.08.009 -
Hydroxyl (O-H) confidence 1.0
“1400 OH Stretch Overtone 1344 SiO 4 1050 Fe-O-Si/Si-O-Si”
do Nascimento-Dias 等 - 2020 - Detection of organic or inorganic material in Mart DOI: 10.1017/S147355042000021X -
Alkyl C-H confidence 1.0
“cm-1 In the case of pure PEO, for the distinctive peaks between 800-1400 in the spectrum, the cm-1, stretching vibration peak of C-O-C splits into three peaks at 1146, 1110, and 1062 and the two cm-1 bands appeared at 1344, and 1359 can be”
Preparation and Composition Optimization of PEO:MC Polymer Blend Films to Enhance Electrical Conductivity DOI: 10.3390/polym11050853 -
Aromatic ring confidence 1.0
“The symmetrical stretching frequency of the benzene rings become intense at 1555 The C=C symmetrical conjugated bond stretching frequency of the benzene rings becomes intense at 1344 cm-1.”
Aktas 等 - 2020 - A Novel Ag-N-Heterocyclic Carbene Complex Bearing DOI: 10.3390/cryst10030171 -
Alkyl C-H confidence 1.0
“cm1 cm1 cmprincipal bands at 3561, 3496 (stretching of O-H bonds), 1724 (stretching of C = O), 1344 1 cm1 cm1 (bending of C-H bonds), 1282, 1269, 1251 (stretching of C-O bonds), and 1046 (stretching of”
Ali 等 - 2023 - Nitazoxanide and azithromycin for the early treatm DOI: 10.21203/rs.3.rs-1745239/v1
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