What absorbs at 1229 cm⁻¹ in an FTIR spectrum?
A band near 1229 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 1229 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 | 9 | 9 | 1,0 |
| Methacrylate | 9 | 9 | 1,0 |
| Acetate | 9 | 9 | 1,0 |
| Methoxy (OCH3) | 8 | 8 | 1,0 |
| Amide | 4 | 4 | 1,0 |
| Hydroxyl (O-H) | 3 | 3 | 1,0 |
| Alkyl C-H | 2 | 2 | 1,0 |
| Secondary amine | 2 | 2 | 1,0 |
| C n single bond | 2 | 2 | 1,0 |
| Carboxyl (COOH) | 2 | 2 | 1,0 |
| Carbonyl (C=O) | 2 | 2 | 1,0 |
| C c single bond | 1 | 1 | 1,0 |
| N h | 1 | 1 | 1,0 |
| Bromine | 1 | 1 | 1,0 |
| Carbon bromine | 1 | 1 | 1,0 |
| Ketone | 1 | 1 | 1,0 |
| Ester | 1 | 1 | 1,0 |
| Urethane | 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 |
|---|---|---|---|
| alginate | 1229, 1100, 1715 | 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 1229 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
“of peak changes in wavenumber for alginate-GA in BBPEs system (cm-1) Assignments (functional group) Wavenumber GA ALGAALGAALGAALGAALGAALGAALGA0 1 2 3 4 5 6 - C-O-C 1025 1030 1031 1035 1035 1080 1081 stretching - - - - - - - 1074 C-O stretch”
Enhancing proton conductivity of sodium alginate doped with glycolic acid in bio-based polymer electrolytes system DOI: 10.1007/s10965-020-02142-0 -
Acetate confiança 1,0
“Meanwhile, the peaks at 1229 and 1070 are assigned to C-O and C-O-C stretching vibrations cm-1 from urethane carbonyl.”
Preparation of one-shot and two-shot method of semi-rigid polyurethane film based on functionalized liquid natural rubber DOI: 10.1063/1.5047200 -
Acetate confiança 1,0
“The bands at 1229 and cm-1 samples was examined immediately after the sam1062 are assigned to C-O and C-O-C stretching ples were removed from the media before they were vibrations from urethane carbonyl [9].”
The behavior of semi-rigid polyurethane film based on functionalized rubber by one-shot and two-shot method preparation DOI: 10.1007/s10853-018-2578-8 -
Carboxyl (COOH) confiança 1,0
“The degree of stretching vibration mode of the carboxylic group (C-O) corresponding to the peaks at 1229, 1217, 1215, 1073, cm-1 1071 and 1068 of all as-burnt BCZT powders decreased with increasing pH value.”
Influence of pH values on the surface and properties of BCZT nanopowders synthesized via sol-gel auto-combustion method DOI: 10.1016/j.surfcoat.2016.03.091 -
C-O single bond confiança 1,0
“LLM confirmed rule peak-group candidate”
Graphene oxide-TiO2 and reduced graphene oxide-TiO2 nanocomposites: Insight in charge-carrier lifetime measurements DOI: 10.1016/j.cattod.2016.11.008 -
confiança 1,0
“cm(cid:0) C-- 1, 8400 automatic nitrogen determination apparatus (FOSS, Hiller, which correspond to the O stretching vibra1229, and 1059 C(cid:0) (cid:0) (cid:0) C(cid:0) O(cid:0) Denmark) in the Kjeldahl mode.”
Preparation of pH-sensitive polylactic acid-naringin coaxial electrospun fiber membranes for maintaining and monitoring salmon freshness DOI: 10.1016/j.ijbiomac.2021.08.087 -
Acetate confiança 1,0
“hydrogen bonded hydroxyl groups (3600-3200 cm-1 The standard has a very strong band at 1737 that is assigned to C=O cm-1 that corresponds to in-plane stretching of COOH group and a band at 1229 bending vibrations of OH groups from COOH (Fig”
Miletic 等 - 2020 - Oxidized humic acids from the soil of heat power p DOI: 10.2298/JSC190726099M -
Amide confiança 1,0
“LLM confirmed rule peak-group candidate”
Direct Quantification of Drug Loading Content in Polymeric Nanoparticles by Infrared Spectroscopy DOI: 10.3390/pharmaceutics12100912
Tem um espectro com esta banda?
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