What absorbs at 2815 cm⁻¹ in an FTIR spectrum?
A band near 2815 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 3 cited sources
Possible functional-group assignments
| Functional group | Supporting facts | Cited sources | Top confidence |
|---|---|---|---|
| Alkyl C-H | 2 | 1 | 1.0 |
| Aldehyde (CHO) | 1 | 1 | 1.0 |
| Aromatic ring | 1 | 1 | 1.0 |
| Lignin | 1 | 1 | 1.0 |
Ranking reflects accumulated literature evidence, not a single authoritative rule. Always confirm against your sample context.
Literature behind these assignments
-
Lignin confidence 1.0
“This fact may be explained by of methyl and methylene groups respectively whereas the two minor C\\H cm-1 two reasons: the sample used in the measurement may not havebeen bands between 2815 and 2850 are assigned to symmetric C\\H concentrat”
Comprehensive characterization of industrial wastewaters using EEM fluorescence, FT-IR and 1H NMR techniques DOI: 10.1016/j.scitotenv.2021.150417 -
Alkyl C-H confidence 1.0
“The second dominant band at 2815 can be ascribed to C-H stretching of aldehyde cm-1, cm-1, cm-1 C≡C, functional group.”
Green synthesis and characterization of Fe3O4 nanoparticles using Chlorella-K01 extract for potential enhancement of plant growth stimulating and antifungal activity DOI: 10.1038/s41598-021-01538-2 -
confidence 0.9
“Explicit assignment in text.”
Cleavage of the main carbon chain backbone of high molecular weight polyacrylamide by aerobic and anaerobic biological treatment DOI: 10.1016/j.chemosphere.2017.09.079
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