What absorbs at 1748 cm⁻¹ in an FTIR spectrum?
A band near 1748 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) | 4 | 3 | 0.95 |
| Aldehyde (CHO) | 1 | 1 | 0.9 |
Ranking reflects accumulated literature evidence, not a single authoritative rule. Always confirm against your sample context.
Literature behind these assignments
-
confidence 1.0
“Explicit assignment: 'high-frequency peak at 1748 from the symmetric stretching vibration of the two carbonyl groups'.”
Park 和 Ji - 2011 - Ultrafast Vibrational Population Transfer Dynamics DOI: 10.1002/cphc.201000794 -
confidence 1.0
“Explicitly assigned as C=O carboxylic band.”
Ardelean 等 - 2022 - New Polymeric Adsorbents Functionalized with Amino DOI: 10.3390/molecules27092894 -
Carbonyl (C=O) confidence 0.9
“Characteristic for C=O.”
Sangadah 等 - 2018 - Enzymatic Synthesis of Glycerol Ester Hydrolyzed C DOI: 10.1063/1.5064108 -
confidence 0.9
“Explicit assignment.”
Abouzeid 等 - 2022 - PREPARATION AND PROPERTIES OF NOVEL BIOCOMPATIBLE DOI: 10.1615/CritRevBiomedEng.v40.i5.10 -
Carbonyl (C=O) confidence 0.9
“Characteristic absorption at 1748 cm-1 for CFT molecules.”
Kawish 等 - 2020 - Enhancement in Oral Absorption of Ceftriaxone by H DOI: 10.3390/pharmaceutics12060492 -
Aldehyde (CHO) confidence 0.9
“Snippet: '1748 represented the release of aldehydes'”
Pan 和 Jiang - 2019 - Evaluating the Effects of KCl on Thermal Behavior DOI: 10.3390/ma12111826 -
confidence 0.8
“Shift in the peak at 1748 cm-1 related to PLA's crystallinity.”
Orellana-Barrasa 等 - 2022 - The Mechanical, Thermal, and Chemical Properties o DOI: 10.3390/polym14245414 -
Carbonyl (C=O) confidence 0.7
“Peak due to oil”
Chippie 等 - 2002 - Quantitative analysis of fat and moisture in mayon DOI: 10.1081/JFP-120015499
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