Urea — FTIR absorption peaks and assignments
These are the characteristic FTIR wavenumbers where Urea tends to absorb, compiled from published literature and ranked by supporting evidence. Each assignment is traceable to a source (DOI) and cross-validated against our 130,000+ reference spectra and knowledge graph.
Backed by 8 cited sources
Resposta rápida
Urea is usually assigned by looking for a recurring cluster of characteristic peaks rather than one exact textbook number. The table below shows where the literature most often places this group in FTIR, ranked by accumulated evidence.
Characteristic FTIR peaks for Urea
| Número de onda (cm⁻¹) | Fatos de suporte | Fontes citadas | Maior confiança |
|---|---|---|---|
| 1619 | 2 | 2 | 1,0 |
| 1450 | 2 | 2 | 1,0 |
| 3300 | 2 | 2 | 1,0 |
| 1635 | 2 | 2 | 1,0 |
| 1639 | 2 | 2 | 1,0 |
| 1640 | 2 | 2 | 1,0 |
| 1645 | 1 | 1 | 1,0 |
| 1707 | 1 | 1 | 1,0 |
| 1682 | 1 | 1 | 1,0 |
| 2063 | 1 | 1 | 1,0 |
| 1647 | 1 | 1 | 1,0 |
| 3335 | 1 | 1 | 1,0 |
| 1582 | 1 | 1 | 1,0 |
| 1107 | 1 | 1 | 1,0 |
| 1663 | 1 | 1 | 1,0 |
| 1587 | 1 | 1 | 1,0 |
| 1057 | 1 | 1 | 1,0 |
| 1658 | 1 | 1 | 1,0 |
| 1686 | 1 | 1 | 1,0 |
| 1065 | 1 | 1 | 1,0 |
| 1650 | 1 | 1 | 1,0 |
| 1634 | 1 | 1 | 1,0 |
| 1685 | 1 | 1 | 1,0 |
| 1703 | 1 | 1 | 1,0 |
| 2850 | 1 | 1 | 1,0 |
| 3100 | 1 | 1 | 1,0 |
| 1670 | 1 | 1 | 1,0 |
| 3410 | 1 | 1 | 1,0 |
| 2918 | 1 | 1 | 1,0 |
| 3351 | 1 | 1 | 1,0 |
Showing the 30 best-supported peaks of 57 total for Urea.
Lógica do espectro
Uma atribuição de grupo funcional se torna mais confiável quando várias bandas esperadas aparecem juntas. Use esta página para encontrar os picos com maior suporte e, em seguida, confirme que a mesma amostra exibe um padrão coerente, em vez de um único pico isolado.
Uso no mundo real
Estas páginas são úteis para análise de material desconhecido, explicação de picos em relatórios, solução de problemas de polímeros e verificação se uma família de materiais candidata é quimicamente plausível.
Erros comuns
- Usar uma página de grupo funcional como veredito completo do material sem verificar o resto do espectro.
- Assumindo que a banda mais forte é sempre a mais diagnóstica.
- Esquecer que processamento, aditivos, envelhecimento e misturas podem deslocar ou alargar os picos esperados.
Conselho de verificação
Use DSC, GC-MS ou TGA quando várias famílias de materiais compartilham bandas semelhantes ou quando efeitos de mistura tornam a atribuição FTIR incerta.
Literatura por trás destas atribuições
-
1623 cm⁻¹ confiança 1,0
“Because urea and ChCL intermolecular hydrogen interactions are formed, the stretching vibration of NH2 at 1662 cm-1 and the asymmetric vibration of NH2 at 1606 cm-1 in the FTIR spectra of urea shifted to 1663 and 1623 cm-1, respectively, in”
Can 等 - 2023 - Choline Chloride-Based Deep Eutectic Solvent-Treat DOI: 10.3390/f14030569 -
1635 cm⁻¹ confiança 1,0
“The prominent bonded cm-1 band centred at 1635 corresponds to the hydrogen-bonded ordered urea carbonyl [27].”
Hydrogen bonding and thermomechanical properties of model polydimethylsiloxane based poly(urethane-urea) copolymers: Effect of hard segment content DOI: 10.1016/j.porgcoat.2015.06.015 -
1640 cm⁻¹ confiança 1,0
“Furthermore, the sharp peak at 1640 cm-1, amine-isocyanate generated by the ing at 1640 is attributed to the urea bond created by the reaction reaction, could not be found in the spectrum of the between the amine group and HDI.”
Cohn 和 Stern - 2000 - Sequential surface derivatization of PET films DOI: 10.1021/ma9900784 -
2060 cm⁻¹ confiança 1,0
“3458cm21 17 Local base lines for the urea peak at and the thiocyanate peak 2060cm21 2551cm21 07:56 at were drawn by hand using the points at 3711 and for 1930cm21 the urea peak and 2319 and for the thiocyanate peak, respectively.”
Furlan 等 - 2004 - FTIR analysis of mouse urine urea using IR cards DOI: 10.1081/SL-120038766 -
1639 cm⁻¹ confiança 1,0
“Small band at 1639 belongs to carbonyl (-C=O) with C=O-NH arrangements of traces of urea which may be present due to the reaction of excess isocyanate with moisture in air.”
Preparation and characterization of aliphatic polyurethane and modified hydroxyapatite composites for bone tissue engineering DOI: 10.1007/s00289-019-03067-5 -
1690 cm⁻¹ confiança 1,0
“1690cm-1 absence of peaks at The PU was cast onto the screen-printed electrode (SPE) representing urea (C=O) in and analyzed using a single voltammetric cycle between this study indicated there is no urea formation as a bypro- -1200 and +15”
Munir 等 - 2022 - Design and Synthesis of Conducting Polymer Bio-Bas DOI: 10.1155/2022/6815187 -
1640 cm⁻¹ confiança 1,0
“The H-bonded urea (1640 cm-1) occurring first followed by the free urethane reveals by the free urethane reveals that urea followed the first-order reaction [2].”
Effects of NCO/OH Ratios on Bio-Based Polyurethane Film Properties Made from Acacia mangium Liquefied Wood DOI: 10.3390/polym15051154 -
3197 cm⁻¹ confiança 1,0
“The peak at 3197 is attributed to the overtone of the C=O stretching in urea which is also in Fermi resonance with the N-H stretching mode (Perkins, Painter et al.”
Ternary Natural Deep Eutectic Solvent (NADES) Infused Phthaloyl Starch as Cost Efficient Quasi-Solid Gel Polymer Electrolyte DOI: 10.1016/j.carbpol.2017.03.023
See Urea in your own spectrum
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