What absorbs at 1704 cm⁻¹ in an FTIR spectrum?
A band near 1704 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 |
|---|---|---|---|
| Carbonyl (C=O) | 6 | 5 | 0.95 |
| Metal oxygen | 2 | 1 | 0.9 |
| Carboxyl (COOH) | 1 | 1 | 1.0 |
| C-O single bond | 1 | 1 | 0.9 |
| Alkene (C=C) | 1 | 1 | 0.9 |
Ranking reflects accumulated literature evidence, not a single authoritative rule. Always confirm against your sample context.
Literature behind these assignments
-
Carboxyl (COOH) confidence 1.0
“Explicit assignment in text”
Meng 等 - 2019 - Kinetics and Thermodynamics of Uranium (VI) Adsorp DOI: 10.3390/ijerph16091552 -
Carbonyl (C=O) confidence 0.95
“Explicit assignment in text: 'absorption peak at 1704 representing the -C=O stretching vibration'”
Kang - 2014 - Concentration effect on the optical absorption and DOI: 10.1117/12.2061447 -
Carbonyl (C=O) confidence 0.9
“Explicit assignment in text.”
Kim 和 Kang - 2014 - The cause of absorption and luminescence band shif DOI: 10.3938/jkps.64.451 -
Metal oxygen confidence 0.9
“Explicit assignment: 'stretches of Asn105 at 1704' and 'CdO (-)/1700 (+) cm-1'”
Sudo 等 - 2005 - Steric constraint in the primary photoproduct of a DOI: 10.1021/ja056203aCCC -
Alkene (C=C) confidence 0.9
“Chromophore assignment for C=C at 1704 cm-1.”
van Thor 等 - 2005 - Assignments of the Pfr-Pr FTIR difference spectrum DOI: 10.1021/jp052323t -
C-O single bond confidence 0.9
“Text: 'CO (1704)'”
Barakat 等 - 2020 - Synthesis, X-ray Single Crystal, Conformational An DOI: 10.3390/cryst10020120 -
Carbonyl (C=O) confidence 0.9
“C=O bond stretches”
Ferreira da Silva Neto 等 - 2021 - DOI: 10.18273/revion.v34n2-2021009 -
Carbonyl (C=O) confidence 0.9
“Text states 'where C=O is located' at 1704 cm-1.”
Guo 和 Tsai - 2015 - Analysis on Thermal Hazard of Foam Decoration Mate DOI: 10.1155/2015/168143
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