What absorbs at 1143 cm⁻¹ in an FTIR spectrum?
A band near 1143 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
Possible functional-group assignments
| Functional group | Supporting facts | Cited sources | Top confidence |
|---|---|---|---|
| Methacrylate | 8 | 8 | 1.0 |
| Acetate | 8 | 8 | 1.0 |
| C-O single bond | 8 | 8 | 1.0 |
| Methoxy (OCH3) | 7 | 7 | 1.0 |
| Alkyl C-H | 5 | 5 | 1.0 |
| Aromatic ring | 3 | 3 | 1.0 |
| Amide | 2 | 2 | 1.0 |
| Hydroxyl (O-H) | 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-O bond | 1 | 1 | 1.0 |
| S eq o | 1 | 1 | 1.0 |
| Ring structure | 1 | 1 | 1.0 |
| Lignin | 1 | 1 | 1.0 |
| Water (H2O) | 1 | 1 | 1.0 |
| Phosphorus | 1 | 1 | 1.0 |
| Phosphate (PO4) | 1 | 1 | 1.0 |
| C c single bond | 1 | 1 | 1.0 |
| N h | 1 | 1 | 1.0 |
| Sulfate (SO4) | 1 | 1 | 0.8 |
Ranking reflects accumulated literature evidence, not a single authoritative rule. Always confirm against your sample context.
Literature behind these assignments
-
Alkyl C-H confidence 1.0
“Major infra-red spectral peaks of PVA (2946.67 stretching of C-H, 1142.72 cm-1;”
Sprayed in-situ synthesis of Polyvinyl alcohol/Chitosan loaded Silver nanocomposite hydrogel for improved antibacterial effects DOI: 10.1016/j.ijbiomac.2019.09.186 -
confidence 1.0
“3 Effect of pH (A) and temperature (B) on the decolorization of MB by strain Acinetobacter pittii cm-1, the MB was reported at 2350 while the absorption corresponding to the H-N-H bending cm-1.Thesepeaks werealsosignificantly reducedin thes”
Biodegradation of Methylene Blue as an Evidence of Synthetic Dyes Mineralization during Textile Effluent Biotreatment by Acinetobacter pittii DOI: 10.1007/s40710-020-00443-6 -
Acetate confidence 1.0
“are 1143, 1079, 927, and 862 the internal structure of the grain, given that through miThe bands at 1143 and C-O-C C-OH cm-1 croscopy it was found that the granule maintains its 1079 correspond to and stretching”
Roa Acosta 等 - 2020 - Structural and thermal properties of the amaranth DOI: 10.1515/ijfe-2020-0024 -
Phosphate (PO4) confidence 1.0
“1143cm-1 phosphate band.”
Spevak 等 - 2013 - Fourier Transform Infrared Spectroscopic Imaging P DOI: 10.1007/s00223-013-9695-9. -
Hydroxyl (O-H) confidence 1.0
“cm-1 cm-1 absorption at 1639 of O-H type from bound water molecules and bands at 1143, 1073 and 1024 due vibrations of the C-O-C from glycosidic bonds and O-H of alcohols.”
Vasconcelos Silva 等 - 2019 - Nanostructured polymeric system based of cashew gu DOI: 10.1590/S1517-707620190003.0712 -
confidence 1.0
“Energy band gap determination of ZnO films sintered cm-1 The 1143 is attributed to Zn-OH stretching and at different temperatures with diffused reflectance spectra the appearance of this peak shows the adsorption”
Investigation of physical properties of screen printed nanosized ZnO films for optoelectronic applications DOI: 10.1051/epjap/2015150019 -
Acetate confidence 1.0
“N C H O cm-1 1032 Aromatic C-H deformation, C-O deformation COS 0,03 46,11 6,00 47,87 cm-1 1143 Vibration in C-O-C Cellulose and Hemicellulose TW1 0,04 47,06 5,99 46,91 cm-1 1226 C= resistance and syringyl ring in lignin and xylan TW2 0,65”
Aytin 等 - 2022 - Chemical, Hygroscopic, and Mechanical Properties o DOI: 10.15376/biores.17.1.785-801 -
Aromatic ring confidence 1.0
“A peak at 1143 corresponding to aromatic C-H stretching, and cm-1 the band at 795 are also observed due to the CH rocking of phenolic compounds.”
The “End Life” of the Grape Pomace Waste Become the New Beginning: The Development of a Virtuous Cycle for the Green Synthesis of Gold Nanoparticles and Removal of Emerging Contaminants from Water DOI: 10.3390/antiox11050994
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