What absorbs at 1252 cm⁻¹ in an FTIR spectrum?
A band near 1252 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 1252 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 |
|---|---|---|---|
| Methacrylate | 8 | 7 | 1.0 |
| Acetate | 8 | 7 | 1.0 |
| Methoxy (OCH3) | 7 | 6 | 1.0 |
| C-O single bond | 7 | 6 | 1.0 |
| Amide | 6 | 5 | 1.0 |
| Secondary amine | 4 | 3 | 1.0 |
| Hydroxyl (O-H) | 4 | 3 | 1.0 |
| C c single bond | 3 | 3 | 1.0 |
| C n single bond | 3 | 2 | 1.0 |
| Alkyl C-H | 2 | 2 | 1.0 |
| Lignin | 2 | 2 | 1.0 |
| Ketone | 1 | 1 | 1.0 |
| Ester | 1 | 1 | 1.0 |
| Carboxyl (COOH) | 1 | 1 | 1.0 |
| Carbonyl (C=O) | 1 | 1 | 1.0 |
| N h | 1 | 1 | 1.0 |
| Hydrogen bond | 1 | 1 | 1.0 |
| Oxygen heterocycle | 1 | 1 | 1.0 |
| Ring structure | 1 | 1 | 1.0 |
| Nitrate | 1 | 1 | 1.0 |
Ranking reflects accumulated literature evidence, not a single fixed rule. Always confirm against your sample context.
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 1252 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
-
Nitrate confidence 1.0
“cm.-1 cm-1 1248, 1292, 1500, 1625, and 3380 The peak at 1144 monodentate nitrate species initially indicated by peaks at 1252 NOcan be assigned to the formation of species on the surface cm-1 and 1295 shift to lower wavenumbers as the tempe”
Pena 等 - 2004 - Identification of surface species on titania-suppo DOI: 10.1021/jp0313122 -
Acetate confidence 1.0
“The broadpeak at 1252 that corresponds to C-O vibration [16].”
Salem 等 - 2017 - Study of the effect of surface treatment of kenaf DOI: 10.1088/1742-6596/908/1/012001 -
Amide confidence 1.0
“Collagen-specific amide bands Amide I (C = O stretching), Amide II and Amide III (N = H deformation) were identified at 1650-1740, stretching), Amide II and Amide III (N = H deformation) were identified at 1650-1740, 1541 and 1252 cm-1, res”
The Effect of Low-Processing Temperature on the Physicochemical and Mechanical Properties of Bovine Hydroxyapatite Bone Substitutes DOI: 10.3390/ma15082798 -
Acetate confidence 1.0
“The peaks at 1252, 1060 showed cose (Glu), mannose (Man), galactose (Gal), xylose (Xyl), cm-1 the existence of C-O bonds.”
Optimization of food-grade medium for co-production of bioactive substances by Lactobacillus acidophilus LA-5 for explaining pharmabiotic mechanisms of probiotic DOI: 10.1007/s13197-020-04894-5 -
Hydroxyl (O-H) confidence 1.0
“cm-1 C-H aliphatic stretching from -CH and -CH the peak at 1690 is due to C=O cm-1 stretching from -COOH, the peak at 1644 is due to C=C stretching [5], the peak at cm-1 cm-1 1252 is due to O-H bending in a hydroxyl group, and the peak at 1”
Physicochemical Characterization and Antibacterial Activity of Titanium/Shellac-Coated Hydroxyapatite Composites DOI: 10.3390/coatings12050680 -
Amide confidence 1.0
“1310 bonded C =O groups, which increased after RB treat- (C =O vibrations), 1252 (C-N and C-O stretching);”
Iliadi 等 - 2022 - Epsilon ffect of cleansers on the composition and DOI: 10.1186/s40510-022-00449-w -
Amide confidence 1.0
“LLM confirmed rule peak-group candidate”
Purification and Structural Characterization of the Central Hydrophobic Domain of Oleosin* DOI: 10.1074/jbc.M202721200 -
Acetate confidence 1.0
“cm-1 There were also found non-identified bands at 1350 and 1289 The band at 1252 would be due cm-1 to vibration of C-O group of polyols, such as hydroxyflavonoids [25].”
Oliveira 等 - 2016 - FTIR analysis and quantification of phenols and fl DOI: 10.1590/S1517-707620160003.0072
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.