What absorbs at 1976 cm⁻¹ in an FTIR spectrum?
A band near 1976 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 3 cited sources
Quick answer
A band near 1976 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 |
|---|---|---|---|
| Aromatic ring | 1 | 1 | 1,0 |
| Methoxy (OCH3) | 1 | 1 | 1,0 |
| Methacrylate | 1 | 1 | 1,0 |
| Acetate | 1 | 1 | 1,0 |
| C-O single bond | 1 | 1 | 1,0 |
| C c single bond | 1 | 1 | 1,0 |
| Amide | 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.
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 1976 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 por trás destas atribuições
-
C c single bond confiança 1,0
“C-C Absorption Lines cm-1, All the diamond samples showed clear absorptions between 1970 and 2300 which were the vibration absorption of C-C, mainly at 1976, 2027 and 2158, among which”
Cai 等 - 2021 - Microdiamonds in Alkalic Dolerites from the North DOI: 10.3390/cryst11111325 -
C-O single bond confiança 1,0
“The spectra of pentoses (arabinose and xylose) were 210 cm-1, dominated by a band at 991 and 1034 respectively, mainly due to the ν(C-C), 211 ν(C-O) and β(C-CH) vibrations (Edwards, 1976).”
Revisiting the contribution of ATR-FTIR spectroscopy to characterize plant cell wall polysaccharides DOI: 10.1016/j.carbpol.2021.117935 -
Aromatic ring confiança 1,0
“(cid:55)(cid:75)(cid:72)(cid:3)(cid:20)(cid:25)(cid:19)(cid:19)(cid:3)(cid:3013)(cid:3)(cid:20)(cid:24)(cid:27)(cid:24)(cid:3)(cid:70)(cid:80)-1(cid:3)(cid:68)(cid:81)(cid:71)(cid:3)(cid:20)(cid:24)(cid:19)(cid:19)(cid:3)(cid:3013)(cid:3)(c”
Sumathirathne 和 Karunanayake - 2017 - Synthesis of novel porous tannin-phenol-formaldehy DOI: 10.4038/jnsfsr.v45i3.8186
Tem um espectro com esta banda?
Carregue seu espectro FTIR e obtenha um relatório de interpretação completo — atribuições de picos com citações da literatura, correspondências de biblioteca e uma cadeia de evidências com nível de confiança — em segundos.