What absorbs at 3120 cm⁻¹ in an FTIR spectrum?
Una banda cerca de 3120 cm⁻¹ puede apuntar a varios grupos funcionales. A continuación se muestran las asignaciones más probables, clasificadas por cuánta evidencia publicada respalda cada una — cada una trazable a literatura (DOI) y validada de forma cruzada con nuestros más de 130,000 espectros de referencia y grafo de conocimiento.
Backed by 7 cited sources
Quick answer
A band near 3120 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.
Posibles asignaciones de grupos funcionales
| Grupo funcional | Hechos de respaldo | Fuentes citadas | Confianza máxima |
|---|---|---|---|
| Hydroxyl (O-H) | 3 | 2 | 1,0 |
| N h | 2 | 2 | 1,0 |
| Alkyl C-H | 1 | 1 | 1,0 |
| Methacrylate | 1 | 1 | 1,0 |
| Ketone | 1 | 1 | 1,0 |
| Ester | 1 | 1 | 1,0 |
| Carboxyl (COOH) | 1 | 1 | 1,0 |
| Carbonyl (C=O) | 1 | 1 | 1,0 |
| Amide | 1 | 1 | 1,0 |
| Acetate | 1 | 1 | 1,0 |
| Secondary amine | 1 | 1 | 1,0 |
La clasificación refleja la evidencia acumulada de la literatura, no una única regla autorizada. Siempre confirme según el contexto de su muestra.
Possible materials
| Material | Supporting peaks | Overlapping groups | Fuentes citadas |
|---|---|---|---|
| polyurethane | 3120, 2270, 1700 | Alkyl C-H, Methacrylate, N h | 1 |
| polysaccharide | 3120, 1637, 1320 | Methacrylate, Hydroxyl (O-H), Alkyl C-H | 1 |
| PANI | 3120, 2930, 1300 | Alkyl C-H, N h | 1 |
Materials are shown only when the same literature pool supports this band and at least one additional characteristic peak.
Spectrum logic
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 3120 cm⁻¹ is usually not enough for material identification by itself.
Real-world usage
This type of query is common in polymer identification, unknown plastic screening, QC troubleshooting, recycled-material verification, and literature-backed peak assignment review.
Common mistakes
- Treating one isolated band as proof of a material without checking at least one or two supporting peaks.
- Ignoring overlap: multiple functional groups can contribute near the same wavenumber.
- Skipping validation when additives, blends, oxidation, or contamination may distort the spectrum.
Verification advice
When ambiguity remains, validate the hypothesis with DSC, GC-MS, or TGA, especially for blends, degraded samples, and filled polymers.
Literatura detrás de estas asignaciones
-
Secondary amine confianza 1,0
“The N-H) of the thioamide and amide can be observed at asymmetric stretching vibration of the secondary amine (ν 3177cm-1 3120cm-1 and respectively.”
Adan 等 - 2014 - Synthesis, Characterization and Antibacterial Stud DOI: 10.1063/1.4895199 -
Hydroxyl (O-H) confianza 1,0
“The vibrational bands at between between 3680 cm-1 and 3120 cm-1 are due to O-H and N-H stretching and can be attributed to cm-1 cm-1 between 3680 cm-1 and 3120 cm-1 are due to O-H and N-H stretching and can be attributed to 3680 and 3120 a”
Self-Healable Supramolecular Vanadium Pentoxide Reinforced Polydimethylsiloxane-Graft- Polyurethane Composites DOI: 10.3390/polym11010041 -
Hydroxyl (O-H) confianza 1,0
“cm(cid:3)1 3000-3550 467 In the range, a strong and wide -OH absorption band can be seen, which corresponds to stretchingvibrations.Thepeaksat3120and2980cm(cid:3)1thatcan be observed in Fig.”
Synthesis and characterization of a novel ruthenium(ii) trisbipyridine complex magnetic nanocomposite for the selective oxidation of phenols DOI: 10.1039/c9ra05079e -
Acetate confianza 1,0
“The asymmetric and symmetric stretching CH3 C=O stretching of CH group and band vibrations were found at 3120 and 1670-1665 3”
Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (FTIR) and Artificial Neural Networks Applied to Investigate Quantitative Changes of Selected Soluble Biomarkers, Correlated with H. pylori Infection in Children and Presumable Consequent Delayed Growth DOI: 10.3390/jcm9123852 -
Alkyl C-H confianza 1,0
“LLM confirmed rule peak-group candidate”
Mucilage from Yellow Pitahaya (Selenicereus megalanthus)Fruit Peel: Extraction, Proximal Analysis, and Molecular Characterization DOI: 10.3390/molecules28020786 -
confianza 1,0
“The 3409cm-1 3120cm-1 1614cm-1 the peaks at peak at and are attributed to Nrepresents the N-H bend vibration.”
Zhu 等 - 2013 - Electrochemical Properties of PANI as Single Elect DOI: 10.1155/2013/940153 -
confianza 0,8
“Observed band assigned to C-H.”
Density Functional Theory and Molecular Docking Investigations of the Chemical and Antibacterial Activities for 1-(4-Hydroxyphenyl)-3-phenylprop-2-en-1-one DOI: 10.3390/molecules26123631
¿Tiene un espectro con esta banda?
Cargue su espectro FTIR y obtenga un informe de interpretación completo — asignaciones de picos con citas bibliográficas, coincidencias de librerías y una cadena de evidencia con calificación de confianza — en segundos.