What absorbs at 1627 cm⁻¹ in an FTIR spectrum?
A band near 1627 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 |
|---|---|---|---|
| Amide | 4 | 4 | 0.9 |
| Alkene (C=C) | 3 | 3 | 1.0 |
| Carbonyl (C=O) | 1 | 1 | 0.9 |
| Water (H2O) | 1 | 1 | 0.9 |
| C=n | 1 | 1 | 0.9 |
| N h | 1 | 1 | 0.8 |
| Aromatic ring | 1 | 0 | 0.9 |
| Protein beta sheet | 1 | 0 | 0.7 |
Ranking reflects accumulated literature evidence, not a single authoritative rule. Always confirm against your sample context.
Literature behind these assignments
-
Alkene (C=C) confidence 1.0
“Explicit assignment in text.”
Mangeli 等 - 2021 - Decontamination of fenitrothion from aqueous solut DOI: 10.1007/s40201-021-00706-w -
confidence 1.0
“explicit assignment”
Roy 等 - 2010 - Processing of type I collagen gels using nonenzyma DOI: 10.1002/jbm.a.32231. -
confidence 0.9
“Explicit assignment: 'free carboxyl band at 1627'.”
Khaksar 等 - 2014 - Nisin-loaded alginate-high methoxy pectin micropar DOI: 10.1111/ijfs.12516 -
Alkene (C=C) confidence 0.9
“Explicit assignment: 'ν (C=C)'.”
Kusrini 等 - 2020 - Synthesis, characterization, and performance of gr DOI: 10.1016/j.apsusc.2019.145005 -
confidence 0.9
“Explicit assignment: peak at 1627 cm-1 corresponds to sp2-hybridization C=C in graphene.”
Yakovleva 等 - 2022 - SORPTION OF COPPER (II) CATIONS FROM AQUEOUS SOLUT DOI: 10.6060/ivkkt.20226505.6543 -
C=n confidence 0.9
“C=N bending.”
Ahmed 等 - 2023 - A Comprehensive Approach to Derivatization Elemen DOI: 10.3390/molecules28031406 -
Water (H2O) confidence 0.9
“Text: 'peaks centred at 1627cm are characteristic of δ-H2O bending'”
Bagheri 等 - 2013 - Synthesis and Characterization of Anatase Titanium DOI: 10.1155/2013/848205 -
Amide confidence 0.9
“Explicit assignment in text: 'intense amide I peak at around 1627 cm-1'”
Insuasty 等 - 2015 - Supramolecular One-Dimensional np-Nanofibers DOI: 10.1038/srep14154
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