What absorbs at 1494 cm⁻¹ in an FTIR spectrum?
A band near 1494 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 1494 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 |
|---|---|---|---|
| Alkyl C-H | 4 | 4 | 1,0 |
| Amide | 4 | 4 | 1,0 |
| Aromatic ring | 4 | 3 | 1,0 |
| Ring structure | 3 | 3 | 1,0 |
| N h | 3 | 3 | 1,0 |
| Secondary amine | 3 | 3 | 1,0 |
| C n single bond | 3 | 3 | 1,0 |
| Carboxyl (COOH) | 2 | 2 | 1,0 |
| Methyl | 2 | 2 | 1,0 |
| Alkene (C=C) | 2 | 2 | 1,0 |
| Carbonyl (C=O) | 2 | 2 | 1,0 |
| Lipid | 1 | 1 | 1,0 |
| Nitro (NO2) | 1 | 1 | 1,0 |
| Hydroxyl (O-H) | 1 | 1 | 1,0 |
| Methoxy (OCH3) | 1 | 1 | 1,0 |
| C-O single bond | 1 | 1 | 1,0 |
| Methacrylate | 1 | 1 | 1,0 |
| Ketone | 1 | 1 | 1,0 |
| Ester | 1 | 1 | 1,0 |
| Acetate | 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 |
|---|---|---|---|
| polyaniline | 1494, 1565, 1570 | Aromatic ring, Amide, Alkyl C-H | 2 |
| polyvinylpyrrolidone | 1494, 1660, 1700 | Amide, Alkyl C-H | 1 |
| PLGA | 1494, 3200, 1741 | Alkyl C-H, Amide | 1 |
| montmorillonite | 1494, 1637, 523 | Amide | 1 |
| PVP | 1494, 2983, 1648 | Alkyl C-H, 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 1494 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
-
Acetate confiança 1,0
“2 cm-1 cm-1, 1639 C=O stretching band vibration, 1494 1011 cm-1 cm-1 cm-1 bands, 733 bands, and 438 bands were”
Reactive Oxygen Species (ROS) Are Generated as Organic Contaminants Are Broken Down: SnO DOI: 10.1007/s12668-023-01111-3 -
Ring structure confiança 1,0
“The characteristic absorption peaksarefoundtobeat2922cm-1isduetotheC Hstretching,1566cm-1iscorrespondsto cm-1 cm-1 C stretching vibration of quinoid ring, 1548 for C N bond stretching, 1494 C cm-1 is corresponds to stretching vibration of b”
Patil 等 - 2011 - Electrical Conductivity of PolyanilineNiZnO3 Comp DOI: 10.1080/00150193.2011.620836 -
Alkyl C-H confiança 1,0
“and 1261 A carbonyl functional group C=O Fourier Transform Infrared (FTIR) Technique cm-1 stretching is represented by a band at 1729 cm-1 while a peak at 1494 was attributed to the FTIR spectrum of acrylic coating (AC), HLE and methyl grou”
Zulkifli 等 - 2020 - Corrosion Resistance Evaluation of Acrylic Coating DOI: 10.17576/jkukm-2020-32(2)-14 -
Alkyl C-H confiança 1,0
“The band at 1665 is for C=O, cm-1 a-willemite in the proper formation of phase with all the while the peak at 1494 is ascribed to CH scissors 2 adiffraction peaks indexed to the standard pattern of vibration [51].”
Alibe 等 - 2019 - Effects of polyvinylpyrrolidone on structural and DOI: 10.1007/s10973-018-7874-7 -
confiança 1,0
“On the other hand, the infrared spectrum of between the positive charge of nitrogen in the polymer and AnCl (Figure 2(a)) presents essentially the bands at 1564 and 1494cm-1 the partially negatively charged surface of the clay as reprewhich”
Bekri-Abbes 和 Srasra - 2015 - Electrical and Dielectric Properties of Polyanilin DOI: 10.1155/2015/516902 -
Alkyl C-H confiança 1,0
“Weak bands at 1494 and 1420 ((cid:9)(CH ((cid:9)(CH modes in CH 3) as) and CH 2)) [32].”
Upgrading the PtCu intermetallic compounds: The role of Pt and Cu in the alloy DOI: 10.1016/j.cattod.2019.11.026 -
Aromatic ring confiança 1,0
“The spectra for amlodipine besylate drug (Figure 4b) show peaks at 2964.69 for C-CH stretching, at 1698.53, 3 cm(cid:1)1 cm(cid:1)1 cm(cid:1)1 1676.11 for ester C=O stretching, at 1493.92 for aromatic skeletal stretching, at 1205.55 for Sul”
Formulation, optimization, and characterization of amlodipine besylate loaded polymeric nanoparticles DOI: 10.1177/09673911211056154 -
Amide confiança 1,0
“The PANI spectrum shows characteristic peaks from benzenoid rings cm-1, N=Q=N 1494 C-N band of an aromatic amine and vibration (Qquinoid ring) at 1301 and”
Kukulski 等 - 2020 - A Polymeric Composite Material (rGOPANI) for Acid DOI: 10.3390/polym12051051
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.