What absorbs at 1089 cm⁻¹ in an FTIR spectrum?
A band near 1089 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 1089 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 |
|---|---|---|---|
| C-O single bond | 13 | 12 | 1.0 |
| Methoxy (OCH3) | 12 | 11 | 1.0 |
| Methacrylate | 12 | 11 | 1.0 |
| Acetate | 12 | 11 | 1.0 |
| Silicon-oxygen (Si-O) | 8 | 8 | 1.0 |
| Silicon (Si) | 6 | 6 | 1.0 |
| Phosphate (PO4) | 6 | 5 | 1.0 |
| Siloxane (Si-O-Si) | 3 | 3 | 1.0 |
| Hydroxyl (O-H) | 3 | 2 | 1.0 |
| Phosphorus | 3 | 2 | 1.0 |
| Water (H2O) | 2 | 2 | 1.0 |
| Alkyl C-H | 2 | 1 | 1.0 |
| Nucleic acid | 1 | 1 | 1.0 |
| Alkene (C=C) | 1 | 1 | 1.0 |
| Thiocarbonyl | 1 | 1 | 1.0 |
| Chlorine | 1 | 1 | 1.0 |
| Secondary amine | 1 | 1 | 1.0 |
| C n single bond | 1 | 1 | 1.0 |
| Amide | 1 | 1 | 1.0 |
| C c single bond | 1 | 1 | 1.0 |
| Metal oxygen | 1 | 1 | 1.0 |
| Acetyl | 1 | 1 | 1.0 |
| Sulfate (SO4) | 1 | 1 | 0.9 |
| Perchlorate | 1 | 1 | 0.9 |
| Carboxyl (COOH) | 1 | 0 | 0.8 |
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 |
|---|---|---|---|
| PVA | 1089, 1660, 2930 | Acetate, Methacrylate, C-O single bond | 1 |
| PEG | 1089, 1650, 1342 | Methacrylate, Acetate, C-O single bond | 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 1089 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
-
Silicon-oxygen (Si-O) confidence 1.0
“FTIR spectra showed peaks at 1089 and cm-1, 801 which corresponded to asymmetric and symmetric O-Si-O.”
Fabrication of Biogenic Silica Nanostructures from Sorghum bicolor Leaves for Food Industry Applications DOI: 10.1007/s12633-020-00379-4 -
Acetate confidence 1.0
“The sharp band at 1089 corresponds The PVA used in this work were obtained in powder form to C-O stretching of acetyl group present on the PVA back from M/s.”
Bhajantri 等 - 2006 - Microstructural studies on BaCl2 doped poly(vinyl DOI: 10.1016/j.polymer.2006.03.054 -
Acetate confidence 1.0
“We show that the PEG C O C peak (at 1089 is the main analytically valuable Received in revised form 17 January 2016 band in IR spectra of PEG-containing systems: it is narrow and highly intense, it is well distinguished 18 January 2016 Acce”
New versatile approach for analysis of PEG content in conjugates and complexes with biomacromolecules based on FTIR spectroscopy. DOI: 10.1016/j.colsurfb.2016.01.030 -
confidence 1.0
“1118 stretching 1241 stretching C-O C-O 1089 stretching 1157 stretching”
El Bialy 等 - 2020 - Comparative Toxicological Effects of Biologically DOI: 10.2147/IJN.S241922 -
Silicon (Si) confidence 1.0
“Thus, Si-O cm-1 asymmetrical stretching vibration corresponds to 1089 value of wavenumber, 1850074-4 February 12, 2018 13:40”
Huseynov 等 - 2018 - Fourier transform infrared spectroscopic study of DOI: 10.1142/S0217979218500741 -
Phosphate (PO4) confidence 1.0
“cm-1 cm-1, ≈1230 837, and 805 Phosphate vibrations at and 1089 and backbone vibrations cm-1 cm-1 ≈1030 at and 765 were found to be sensitive to changes in hydration rather than (cid:1)(cid:2)(cid:3)(cid:1)(cid:4)(cid:5)(cid:6)(cid:7)(cid:8)”
Serec 等 - 2021 - Conformational Transitions of Double-Stranded DNA DOI: 10.3390/app11052360 -
Silicon (Si) confidence 1.0
“3O except for having a logical features of uncoated Fe cm-1 4 peak at 1088.8 belongs to the asymmetry stretching much smoother surface and larger particle diameter (about vibration of Si-O-Si, indicated that SiO was successfully 2 600 nm) d”
Wang 等 - 2020 - Evaluation of Different Blood Circulating miRNAs f DOI: 10.1166/jnn.2020.17160 -
Phosphate (PO4) confidence 1.0
“In the FTIR spectrum of B-V-PIL/W, the bands at 1089 and cm-1, 790 which are assigned to the vibration of P-O and W-O-W bonds, respectively approve immobilization 4034.”
Heteroployacid on the composite of boehmite and polyionic liquid as a catalyst for alcohol oxidation and tandem alcohol oxidation Knoevenagel condensation reactions DOI: 10.1038/s41598-022-20699-2
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