What absorbs at 1455 cm⁻¹ in an FTIR spectrum?
A band near 1455 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 1455 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 |
|---|---|---|---|
| Alkyl C-H | 32 | 30 | 1.0 |
| Methoxy (OCH3) | 7 | 7 | 1.0 |
| Methyl | 7 | 6 | 1.0 |
| Methacrylate | 6 | 6 | 1.0 |
| Acetate | 6 | 6 | 1.0 |
| Aromatic ring | 5 | 5 | 1.0 |
| Alkene (C=C) | 5 | 4 | 1.0 |
| Amide | 4 | 4 | 1.0 |
| N h | 4 | 3 | 1.0 |
| Nitrogen heterocycle | 4 | 2 | 1.0 |
| Secondary amine | 3 | 3 | 1.0 |
| Lipid | 3 | 3 | 1.0 |
| Lewis acid site | 3 | 0 | 1.0 |
| Hydroxyl (O-H) | 2 | 2 | 1.0 |
| Ring structure | 2 | 2 | 1.0 |
| Protein | 2 | 2 | 1.0 |
| C=n | 2 | 2 | 1.0 |
| C c single bond | 2 | 2 | 1.0 |
| Carboxyl (COOH) | 2 | 1 | 1.0 |
| N-O bond | 2 | 1 | 1.0 |
| C n single bond | 1 | 1 | 1.0 |
| Adsorbed carbon monoxide | 1 | 1 | 1.0 |
| Phosphorus | 1 | 1 | 1.0 |
| Phosphate (PO4) | 1 | 1 | 1.0 |
| Carbonate | 1 | 1 | 1.0 |
| Lignin | 1 | 1 | 1.0 |
| Metal oxygen | 1 | 1 | 1.0 |
| C-O single bond | 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 |
|---|---|---|---|
| PHB | 1455, 3440, 1724 | Alkyl C-H, Methacrylate, Methoxy (OCH3) | 1 |
| PLLA | 1455, 1182, 921 | Alkyl C-H, Methoxy (OCH3), Methacrylate | 1 |
| PLA | 1455, 1650, 1073 | Alkyl C-H, Methacrylate, 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 1455 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
-
Alkyl C-H confidence 1.0
“seen that the CH asymmetric deformation band at 1455”
Effect of processing conditions on the development of morphological features of banded or nonbanded spherulites of poly(3hydroxybutyrate) (PHB) and polylactic acid (PLLA) blends DOI: 10.1002/pen.21991 -
confidence 1.0
“Explicit assignment: '1455cm-1 is assigned to overtone of the antisymmetric Sn-'”
Structural and optical studies of 100MeV Au irradiated thin films of tin oxide DOI: 10.1016/j.nimb.2013.05.053 -
Lipid confidence 1.0
“spect to the height of the Amide I band and (iii) the area of the 1450-1455cm-1 peak as representative for the amount of lipids on the surface.”
Interpersonal differences in the friction response of skin relate to FTIR measures for skin lipids and hydration DOI: 10.1016/j.colsurfb.2020.110883 -
C c single bond confidence 1.0
“The most intense and interesting vibrations from this area are shown by the bands at 1455, 1412, 1345, and cm-1, 1252 which mainly come from the deformation of the O-CH group as well as C-C-H in the carbohydrate”
Identification of sugars and phenolic compounds in honey powders with the use of GC–MS, FTIR spectroscopy, and X-ray diffraction DOI: 10.1038/s41598-020-73306-7 -
C c single bond confidence 1.0
“LLM confirmed rule peak-group candidate”
Two potential uses for silver nanoparticles coated with Solanum nigrum unripe fruit extract: Biofilm inhibition and photodegradation of dye effluent DOI: 10.1016/j.micpath.2017.08.039 -
C=n confidence 1.0
“cm-1 cm-1 650-4000 The bands at 1235 and 1290 were attributed to the C-N+ stretching vibration of polaron structure and delocalisation of π electrons respectively.2 along the PAni backbone, The presence of emeraldine salt state cm-1 cm-1 of”
Mustapa 等 - 2018 - Fabrication of Polyaniline Based Chemical Sensor f DOI: 10.21315/jps2018.29.s1.2 -
Acetate confidence 1.0
“this band was located at 1455 For the amorphous and semicrystalline PLLA samsymmetric deforples, the band related to the CH 3”
Characterization of poly(lactic acid) multifilament yarns. I. The structure and thermal behavior DOI: 10.1002/app.32046 -
N h confidence 1.0
“The (-NH) peak at There is a new peak at shifted to 1,whilst 1315cm-1, 1455cm-1after and the cellulosic framework shifted to 1153, the (-COOH) peak shifted to adsorp-”
Thabede 等 - 2021 - Magnetite Functionalized Nigella Sativa Seeds for DOI: 10.1155/2021/6655227
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