What absorbs at 1755 cm⁻¹ in an FTIR spectrum?
A band near 1755 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
Quick answer
A band near 1755 cm⁻¹ is usually interpreted by checking which functional groups repeatedly co-occur there in the literature, then confirming at least one or two additional peaks in the same sample. This page ranks those assignments by accumulated evidence rather than by a single fixed textbook rule.
Possíveis atribuições de grupos funcionais
| Grupo funcional | Fatos de suporte | Fontes citadas | Maior confiança |
|---|---|---|---|
| Carbonyl (C=O) | 6 | 6 | 1,0 |
| Amide | 5 | 5 | 1,0 |
| Methacrylate | 4 | 4 | 1,0 |
| Acetate | 4 | 4 | 1,0 |
| Ketone | 3 | 3 | 1,0 |
| Ester | 3 | 3 | 1,0 |
| Carboxyl (COOH) | 3 | 3 | 1,0 |
| N h | 2 | 1 | 1,0 |
| Secondary amine | 1 | 1 | 1,0 |
| C n single bond | 1 | 1 | 1,0 |
| N-O bond | 1 | 1 | 1,0 |
| Methoxy (OCH3) | 1 | 1 | 1,0 |
| C-O single bond | 1 | 1 | 1,0 |
| Acetyl | 1 | 1 | 0,95 |
A classificação reflete a evidência acumulada da literatura, não uma única regra autoritária. Sempre confirme com o contexto da sua amostra.
Possible materials
| Material | Picos de suporte | Overlapping groups | Fontes citadas |
|---|---|---|---|
| cellulose acetate | 1755, 1650, 1741 | Acetate, Carbonyl (C=O), Methacrylate | 1 |
| poly(vinyl alcohol) | 1755, 1700, 2993 | Acetate, Methacrylate, Carbonyl (C=O) | 1 |
| CS | 1755, 1645, 1720 | Methacrylate, Acetate, Amide | 1 |
Materials are shown only when the same literature pool supports this band and at least one additional characteristic peak.
Spectrum logic
This band becomes meaningful only when read with its neighboring peaks. In practice, analysts first look at the assignments above, then check whether the same sample also shows other peaks expected for the same structural motif. A lone band near 1755 cm⁻¹ is usually not enough for material identification by itself.
Real-world usage
This type of query is common in polymer identification, unknown plastic screening, QC troubleshooting, recycled-material verification, and literature-backed peak assignment review.
Common mistakes
- Treating one isolated band as proof of a material without checking at least one or two supporting peaks.
- Ignoring overlap: multiple functional groups can contribute near the same wavenumber.
- Skipping validation when additives, blends, oxidation, or contamination may distort the spectrum.
Verification advice
When ambiguity remains, validate the hypothesis with DSC, GC-MS, or TGA, especially for blends, degraded samples, and filled polymers.
Literatura por trás destas atribuições
-
Acetate confiança 1,0
“In the case of MGAJ cm-1, PLA, the presence of oligomer molecules was witnessed by the presence of a peak at 1755 which indicates about the presence of -C=O stretching vibration [9, 10].”
Ghosh 等 - 2020 - Blown films fabrication of poly lactic acid based DOI: 10.1016/j.mtcomm.2019.100737 -
Carbonyl (C=O) confiança 1,0
“precursor (a: PVA, b: PVA-g-OOCO) Compared to the FTIR spectrum of PVA, an extra characteristic peak appears at cm-1 1755 on that of the product (Figure 2), which is assigned to the carbonyl groups of incorporated OOCO.”
Yang 和 Xiao - 2020 - A graft copolymer composed of continuously linked DOI: 10.1016/j.matlet.2020.128345 -
Amide confiança 1,0
“amide vibrations at 1755 and 1712 The amide vibrations of the minor diradical species is Cu2+ slightly different from the diradical species characterized under non-catalytic conditions cm-1)”
Ligand Radical Mediated Water Oxidation by a Family of Copper o -Phenylene Bis-oxamidate Complexes DOI: 10.1021/acs.inorgchem.1c00546 -
Carbonyl (C=O) confiança 1,0
“LLM confirmed rule peak-group candidate”
Danciu 等 - 2015 - Preliminary In Vitro Evaluation of Genistein Chemo DOI: 10.1155/2015/262930 -
Acetate confiança 1,0
“2021, 22, x FOR PEER REVIEW 7 of 23 cell wall carbohydrates, namely glucosamines (chitin and chitosan), glucans, and glucuronans: C-H stretching vibrations (C-H stretching in -CH3 and -CH2 at 2933, 2895, and 2885 cm-1), C=O stretching in es”
Assessment of Biotechnologically Important Filamentous Fungal Biomass by Fourier Transform Raman Spectroscopy DOI: 10.3390/ijms -
Carbonyl (C=O) confiança 1,0
“LLM confirmed rule peak-group candidate”
Synthesis and Characterization of Corn Stover-Based Cellulose Triacetate Catalyzed by Ionic Liquid Phosphotungstate DOI: 10.3390/ijms23126783 -
confiança 1,0
“On the other hand, NO interacting with the OH Cu-OH+ (1898-1880cm-1).[16a,19] group of species is expected at lower frequencies In cm-1 the lower frequency region (1806-1780 cm-1), the IR band at 1755 is associated to Cu+”
Martinez-Franco 等 - 2014 - Synthesis, characterization and reactivity of high DOI: 10.1016/j.jcat.2014.03.018. -
Carbonyl (C=O) confiança 1,0
“In addition, a 3 cm-1 cm-1 peak at 1755 corresponded to the carbonyl group (C=O), while the band at 1244 corresponded to the esters31.”
Improved anti-biofouling resistances using novel nanocelluloses/cellulose acetate extracted from rice straw based membranes for water desalination DOI: 10.1038/s41598-022-08324-8
Tem um espectro com esta banda?
Carregue seu espectro FTIR e obtenha um relatório de interpretação completo — atribuições de picos com citações da literatura, correspondências de biblioteca e uma cadeia de evidências com nível de confiança — em segundos.