What absorbs at 1561 cm⁻¹ in an FTIR spectrum?
A band near 1561 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
Resposta rápida
A band near 1561 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 |
|---|---|---|---|
| N h | 5 | 4 | 1,0 |
| Carboxyl (COOH) | 4 | 4 | 1,0 |
| Amide | 4 | 4 | 1,0 |
| Hydrogen bond | 3 | 2 | 1,0 |
| Ester | 2 | 2 | 1,0 |
| Acetate | 2 | 2 | 1,0 |
| Oxygen heterocycle | 1 | 1 | 1,0 |
| Ring structure | 1 | 1 | 1,0 |
| C c single bond | 1 | 1 | 1,0 |
| Amine primary | 1 | 1 | 1,0 |
| Lipid | 1 | 1 | 1,0 |
| Fatty acid | 1 | 1 | 1,0 |
| Secondary amine | 1 | 1 | 1,0 |
| Alkene (C=C) | 1 | 1 | 1,0 |
| Alkyl C-H | 1 | 1 | 1,0 |
| Methacrylate | 1 | 1 | 1,0 |
| Ketone | 1 | 1 | 1,0 |
| Carbonyl (C=O) | 1 | 1 | 1,0 |
| Hydroxyl (O-H) | 1 | 1 | 1,0 |
A classificação reflete a evidência acumulada da literatura, não uma única regra autoritária. Sempre confirme com o contexto da sua amostra.
Materiais possíveis
| Material | Picos de suporte | Grupos sobrepostos | Fontes citadas |
|---|---|---|---|
| starch | 1561, 1650, 1540 | Amide | 1 |
| graphene | 1561, 1720, 2097 | Amide, Carboxyl (COOH) | 1 |
| CS | 1561, 1645, 1720 | Amide, Carboxyl (COOH) | 1 |
| CA | 1561, 1045, 1650 | Amide, Carboxyl (COOH) | 1 |
| polyaniline | 1561, 1565, 1570 | Amide | 1 |
Os materiais são mostrados apenas quando o mesmo conjunto de literatura suporta esta banda e pelo menos um pico característico adicional.
Lógica do espectro
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 1561 cm⁻¹ is usually not enough for material identification by itself.
Uso no mundo real
Este tipo de consulta é comum em identificação de polímeros, triagem de plásticos desconhecidos, solução de problemas de CQ, verificação de materiais reciclados e revisão de atribuição de picos apoiada pela literatura.
Erros comuns
- Tratar uma banda isolada como prova de um material sem verificar pelo menos um ou dois picos de suporte.
- Ignorando sobreposição: vários grupos funcionais podem contribuir próximo ao mesmo número de onda.
- Ignorar a validação quando aditivos, misturas, oxidação ou contaminação podem distorcer o espectro.
Conselho de verificação
Quando a ambiguidade persistir, valide a hipótese com DSC, GC-MS ou TGA, especialmente para misturas, amostras degradadas e polímeros carregados.
Literatura por trás destas atribuições
-
Hydroxyl (O-H) confiança 1,0
“Moreover, the new absorption peaks at 1372, 1508, 1561 cm-1 nium hydroxide (100 ml) was placed into a 250 ml round bottom and 1692 representing the C N stretching, C C stretching of flask, and then 4.0 g of tetraethoxyorthosilane (TEOS) was”
Stopband attenuation of silica spheres by attaching aniline and polyaniline DOI: 10.1016/j.synthmet.2013.03.007 -
Amide confiança 1,0
“110 × 100, = Index(CI%) (5) Crystallinity responsible for aliphatic CH stretching whereas the band 𝐼 1561cm-1 110 at was attributed to amide stretching of C=O.”
Anusha 和 Fleming - 2016 - Synthesis and Characterization of Chitosan Nanoagg DOI: 10.1155/2016/5379424 -
Alkene (C=C) confiança 1,0
“In the FTIR spectrum of rGO-TEPA, few representative peaks were identified at 1654, In the FTIR spectrum of rGO-TEPA, few representative peaks were identified at 1654, 1561, 1443, and 1186 cm-1, which can be attributed to the C=C stretching”
Cojocaru 等 - 2022 - Electrospun Nanofibrous Membranes Based on Citric DOI: 10.3390/polym14020294 -
N h confiança 1,0
“assigned the band at 1561 for aminopropyltrimethoxisilane SAM Chiang [32] deposited on silica gel to NH deformation modes with strong hydrogen bonding.”
Growth and organization of (3-Trimethoxysilylpropyl) diethylenetriamine within reactive amino-terminated self-assembled monolayer on silica DOI: 10.1016/S0079-6816(00)00024-1. -
confiança 1,0
“The most important element was the cm-1 increase in the intensity of peaks in the range of 3400-3200 wavenumbers, typical for cm-1, the presence of N-H bonds, and the increase in the absorption bands at 1561 and 1519 confirming the increase”
Optimization of Glutathione Adhesion Process to Modified Graphene Surfaces DOI: 10.3390/nano11030756 -
Ester confiança 1,0
“ν(C=O) A (at 1561 and 1410 The ester band in curve (split into two components, cm-1) at 1737 and 1728 is also very weak.”
Fourier Transform Infrared (FTIR) Spectroscopic Analyses of Microbiological Samples and Biogenic Selenium Nanoparticles of Microbial Origin: Sample Preparation Effects DOI: 10.3390/molecules -
Amide confiança 1,0
“The remarkable findings of this cm-1 cm-1 band at 1638 - 1561 amide II band at 1561 and study have been proven to be practically important in the cm-1.”
Koutb 等 - 2021 - Paclitaxel production by endophytic fungus, Neopes DOI: 10.30955/gnj.003839 -
Amide confiança 1,0
“spectrumsindicatehigherphospholipidcontent.Intheinterval Typical gluten bands are Amide I (80 % C-O stretch, 10 % cm-1 cm-1, 3100-2750 C-N stretch) at 1654 Amide II (60 % N-H bend, 30 % bands originating from stretch vibrations of C-Nstretc”
Pourfarzad 等 - 2015 - Serish inulin and wheat biopolymers interactions i DOI: 10.1007/s13197-015-1939-4
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.