What absorbs at 1629 cm⁻¹ in an FTIR spectrum?
A band near 1629 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 |
|---|---|---|---|
| Protein beta sheet | 4 | 4 | 0.9 |
| Amide | 3 | 3 | 1.0 |
| Carbonyl (C=O) | 3 | 3 | 1.0 |
| Water (H2O) | 3 | 1 | 0.9 |
| Ring structure | 2 | 2 | 0.9 |
| N h | 2 | 2 | 0.9 |
| Carboxyl (COOH) | 1 | 1 | 0.9 |
Ranking reflects accumulated literature evidence, not a single authoritative rule. Always confirm against your sample context.
Literature behind these assignments
-
Carbonyl (C=O) confidence 1.0
“Peaks between 1629.45 and 1732.02 characteristic of carbonyl group”
Hamouda 等 - 2020 - Bioprocessing strategies for cost-effective simult DOI: 10.1038/s41598-020-70251-3 -
confidence 1.0
“C-C sp2 vibration”
Wei 等 - 2019 - Graphene Oxide Adsorption Enhanced by Attapulgite DOI: 10.3390/app9071390 -
Amide confidence 1.0
“Text: 'stretching C=O (Amide band I, 1629 cm-1)'.”
Xiao 等 - 2019 - Controllable Crimpness of Animal Hairs via Water-S DOI: 10.3390/polym11010172 -
confidence 0.95
“Band at 1629 cm-1 characteristic of parallel β-sheet conformation.”
Smeralda 等 - 2021 - beta-Amyloid peptide interactions with biomimetic DOI: 10.1016/j.ijbiomac.2021.03.107 -
N h confidence 0.9
“Peak at 1629~1608 cm-1 attributed to NH.”
Liao 等 - 2011 - Synthesis and Characterization of an Aminated D-gl DOI: 10.4028/www.scientific.net/AMR.197-198.65 -
confidence 0.9
“Explicitly stated as hydroxamate peak.”
Omar 等 - 2021 - High-Sensitivity Permeation Analysis of Ultrasmall DOI: 10.1021/acs.bioconjchem.1c00017 -
Amide confidence 0.9
“Explicit assignment in text.”
Toan 等 - 2017 - Salicylic acid-induced accumulation of biochemical DOI: 10.1080/17429145.2017.1291859 -
confidence 0.9
“Text: 'two peaks at 1629 and 1652 due to β-strands and α-helices'”
Yamasaki 等 - 1998 - Pressure-denatured state of Escherichia coli ribon DOI: 10.1021/bi981046w
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