What absorbs at 3306 cm⁻¹ in an FTIR spectrum?
A band near 3306 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 3306 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 |
|---|---|---|---|
| Hydroxyl (O-H) | 4 | 4 | 1,0 |
| N h | 4 | 4 | 1,0 |
| Amide | 2 | 2 | 1,0 |
| Hydrogen bond | 1 | 1 | 1,0 |
| Secondary amine | 1 | 1 | 1,0 |
| Carbohydrate | 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 |
|---|---|---|---|
| PVA | 3306, 1660, 2930 | Hydroxyl (O-H), Amide | 1 |
| Starch | 3306, 1650, 1540 | Hydroxyl (O-H), Amide | 1 |
| nanotube | 3306, 1540, 1080 | Amide, N h, Hydroxyl (O-H) | 1 |
| chitosan | 3306, 1650, 1655 | Amide, Hydroxyl (O-H), N h | 1 |
| silver nanoparticles | 3306, 1636, 1631 | Hydroxyl (O-H), Amide, N h | 1 |
| collagen | 3306, 1408, 1660 | Amide, N h | 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 3306 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
“cm-1 the FTIR (ATR) The broad band at 3306.05 revealed study reported a lower value of crystallinity index From Previous presence of OH group in cellulose [20,21], while the band PALF, which was 13.74% compared to the current study [30].”
Characterization of silane treated Malaysian Yankee Pineapple AC6 leaf fiber (PALF) towards industrial applications DOI: 10.1016/j.jmrt.2020.01.058 -
Hydroxyl (O-H) confiança 1,0
“However, the absorption peaks at 3306 due to stretching of O-H appear in all spectra, where they are belonging to PVA.”
Highly Conductive Polyelectrolyte Membranes Poly(vinyl alcohol)/Poly(2-acrylamido-2-methyl propane sulfonic acid) (PVA/PAMPS) for Fuel Cell Application DOI: 10.3390/polym13162638 -
confiança 1,0
“It exhibits a relatively broad peak at about 3306 cm-1 attributed to the N-H stretching vibrations (with NH involved in”
Evaluation of Water Sorption and Solubility and FTIR Spectroscopy of Thermoplastic Orthodontic Retainer Materials Subjected to Thermoforming and Thermocycling DOI: 10.3390/app13085165 -
Hydroxyl (O-H) confiança 1,0
“TEM 2114, and 1635 The peaks at 3306 and 2114 reveals that the CRE-AgNPs are spherical in shape with a wellcorrespond to the stretching vibration of OH in the alcoholic C�C”
Bakthavatchalam 等 - 2023 - Biogenic Synthesis and Characterization of Silver DOI: 10.1021/acsomega.2c07531 -
confiança 1,0
“Fourier Transform Infrared Spectroscopy (FTIR) Analysis with N-H stretching frequency, occurred at 3304.82 and 3305.90 cm-1 for ASC and PSC, respectively.”
Physicochemical Properties and Biocompatibility Evaluation of Collagen from the Skin of Giant Croaker (Nibea japonica) DOI: 10.3390/md16070222 -
Hydroxyl (O-H) confiança 1,0
“The maximum of hydroxyl band shifts from 3306 cm-1 to 3391 cm-1 in both types of the samples.”
Ziegler-Borowska 等 - 2018 - Photochemical Reactions in Dialdehyde Starch DOI: 10.3390/molecules23123358 -
confiança 0,9
“assigned to -CO-NH-”
Liu 等 - 2013 - Synthesis and Application of a Novel Polyamide Cha DOI: 10.1155/2013/616859 -
N h confiança 0,9
“Explicit assignment: '3305.87 symmetric stretching' and 'N-H'”
Ni -chitosan/carbon nanotube: An efficient biopolymer -inorganic catalyst for selective hydrogenation of acetylene DOI: 10.1016/j.heliyon.2023.e13523
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