What absorbs at 2275 cm⁻¹ in an FTIR spectrum?
A band near 2275 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 6 cited sources
Quick answer
A band near 2275 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.
Possibili assegnazioni di gruppi funzionali
| Gruppo funzionale | Fatti di supporto | Fonti citate | Affidabilità massima |
|---|---|---|---|
| Alkyl C-H | 2 | 2 | 1,0 |
| Lewis acid site | 1 | 1 | 1,0 |
| C c single bond | 1 | 1 | 1,0 |
| Methoxy (OCH3) | 1 | 1 | 1,0 |
| Methacrylate | 1 | 1 | 1,0 |
| C-O single bond | 1 | 1 | 1,0 |
| Acetate | 1 | 1 | 1,0 |
| Isocyanate | 1 | 1 | 1,0 |
| Nitrile | 1 | 1 | 1,0 |
| Hydroxyl (O-H) | 1 | 1 | 1,0 |
La classifica riflette le prove bibliografiche accumulate, non una singola regola autorevole. Conferma sempre nel contesto del tuo campione.
Possible materials
| Materiale | Picchi di supporto | Overlapping groups | Fonti citate |
|---|---|---|---|
| polyurethane | 2275, 2270, 1700 | Alkyl C-H, Methoxy (OCH3) | 1 |
| titanium dioxide | 2275, 1716, 1724 | Alkyl C-H | 1 |
| MCM-41 | 2275, 2170, 1655 | Alkyl C-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 2275 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.
Letteratura dietro queste assegnazioni
-
Hydroxyl (O-H) affidabilità 1,0
“absorption peak at approximately 1700 cm-1, Since the isocynate has strong absorption peak between 2275 ~ 2263 the absence of the characteristic isocynate absorption peak indicates that most of the isocynate reacted with alcohol and formed”
Kim 和 Kang - 2012 - Optical properties of azo-chromophore attached on DOI: 10.1117/12.999810 -
Nitrile affidabilità 1,0
“cm(cid:0) cm(cid:0) (C-- 1 1 peak around 2275 indicates the nitrile group N).”
Biosynthesis of titanium dioxide nanoparticles for the photodegradation of dyes and removal of bacteria DOI: 10.1016/j.ijleo.2020.165728 -
Isocyanate affidabilità 1,0
“LLM confirmed rule peak-group candidate”
Synthesis and Characterization of Mesoporous Silica Functionalized with Calix[4]arene Derivatives DOI: 10.3390/ijms131013726 -
Alkyl C-H affidabilità 1,0
“absorptionat1600cm-1attributedtoaromaticbenzenering, C-5, 7, and 8 at δ 156.8, 156.3, and 94.5, whereas aromatic C 2275cm-1 proton at δ 5.89 (H-8) showed HMBC correlations with strong absorption band at due to C-H stretching H 1255cm-1 C-6,”
Guyasa 等 - 2018 - Antibacterial Activity of Two Flavans from the Ste DOI: 10.1155/2018/5870161 -
Acetate affidabilità 1,0
“corresponds to C-H twisting vibration, C-O/C-O-C/C-C stretching vibration and C-H wagging cm-1, is no sign of isocyanate asymmetric stretch from HDI at 2275 indicating unformed isocyanate β-(1→4) vibration of ester groups and/or glycosidic”
Synthesis and Characterization of Inulin-Based Responsive Polyurethanes for Breast Cancer Applications DOI: 10.3390/polym12040865 -
Lewis acid site affidabilità 1,0
“Besides the band at 2291 - 2296 (Ti+3), CH 3CN molecularly adsorbed on weak Lewis acid sites a band at 2275 - cm-1 attributed to physisorbed acetonitrile was observed in all spectra.”
Adsorption of acetonitrile and its reaction with oxygen on TiO<Subscript>2</Subscript>-supported Au — Rh bimetallic catalysts DOI: 10.1007/s11144-007-5120-6
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