What absorbs at 1262 cm⁻¹ in an FTIR spectrum?
A band near 1262 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 1262 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 |
|---|---|---|---|
| C-O single bond | 8 | 7 | 1,0 |
| Methoxy (OCH3) | 7 | 6 | 1,0 |
| Methacrylate | 7 | 6 | 1,0 |
| Acetate | 7 | 6 | 1,0 |
| Secondary amine | 3 | 2 | 1,0 |
| Amide | 3 | 2 | 1,0 |
| Phosphate (PO4) | 2 | 2 | 1,0 |
| C n single bond | 2 | 1 | 1,0 |
| Alkyl C-H | 2 | 1 | 1,0 |
| Hydroxyl (O-H) | 1 | 1 | 1,0 |
| N h | 1 | 1 | 1,0 |
| Lipid | 1 | 1 | 1,0 |
| Carboxyl (COOH) | 1 | 1 | 1,0 |
| Nucleic acid | 1 | 1 | 1,0 |
| Oxygen heterocycle | 1 | 1 | 1,0 |
| Carbohydrate | 1 | 1 | 1,0 |
| Silicon-oxygen (Si-O) | 1 | 1 | 0,9 |
| Methyl | 1 | 0 | 1,0 |
| Silicon carbon | 1 | 0 | 1,0 |
| Silicon (Si) | 1 | 0 | 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 |
|---|---|---|---|
| MWCNTs | 1262, 3396, 1735 | Methacrylate, Acetate, C-O single bond | 1 |
| polyethylene | 1262, 1737, 1720 | Methacrylate, Acetate, Methoxy (OCH3) | 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 1262 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
-
Carbohydrate confiança 1,0
“The band at 1262 is assigned as -COH in the plane at C-2 and C-3 in cellulose-I and cellulose-II, and it indicates the coexistence of cellulose-I and cellulose-II cm-1 cm-1 in ANFs and RCFs.”
Bian 等 - 2021 - Crystalline Structure Analysis of All-cellulose Na DOI: 10.1007/s10570-017-1259-0 -
Phosphate (PO4) confiança 1,0
“Furthermore, the asymmetric stretching vibration band of P-O-P (at 1262 265 initially shifted to a higher wavenumber (1273 cm-1) when the 266 concentration of yttrium is 0.5 mol.”
Bouabdalli 等 - 2023 - First examination of the influence of Y3+ ions on DOI: 10.21203/rs.3.rs-2052185/v1 -
Acetate confiança 1,0
“The band at 1262 is attributed to the asymmetric and symmetric stretching vibration of (C-O-C) groups belonging to 2-substituted furan rings.”
Edwards 等 - 2018 - Analysis of chemical polymerization between functi DOI: 10.1590/0104-1428.07016 -
Amide confiança 1,0
“stretching of C-N and C=C from acrylic acid at 1262 cm-1.”
Synthesis and in vitro characterizations of porous carboxymethyl cellulose-poly(ethylene oxide) hydrogel film DOI: 10.1186/s40824-015-0033-3 -
C-O single bond confiança 1,0
“ester -C-O-C stretch1262, 1255125512601260ing vinyl 1259 1259 1262 1263, 1229 1236 1236 1227 1229 1229 1238 1238”
Mikolaszek 等 - 2022 - Microscopic and Spectroscopic Imaging and Thermal DOI: 10.3390/polym14142888 -
Nucleic acid confiança 1,0
“The peak at 1262 ternal (IEL) and external elastic lamina (EEL) that could facilitate acthat corresponds to nucleic acid and lipid content has also been assoconfidence.”
Label-Free Discrimination Analysis of De-Differentiated Vascular Smooth Muscle Cells, Mesenchymal Stem Cells and Their Vascular and Osteogenic Progeny Using Vibrational Spectroscopy DOI: 10.1016/j.bbamcr.2017.11.006 -
Acetate confiança 1,0
“In figure 4 (product-B), peak cm-1 C-O value approximately at 1262 corresponds to the stretching mode of bond in the cm-1 32(cid:2) CO group [40].”
Molla 等 - 2022 - Facile extraction and characterization of calcium DOI: 10.1098/rsos.220681 -
Acetate confiança 1,0
“• On addition of MWCNTs and further irradiation, appearance of additional peak at cm-1 1262 is observed which belongs to C-O stretching absorption.”
A Multi-Attribute Decision-Making Model for the Selection of Polymer-Based Biomaterial for Orthopedic Industrial Applications DOI: 10.3390/polym14051020
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