What absorbs at 2162 cm⁻¹ in an FTIR spectrum?
A band near 2162 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 5 cited sources
Quick answer
A band near 2162 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.
Possible functional-group assignments
| Functional group | Supporting facts | Cited sources | Top confidence |
|---|---|---|---|
| Alkene (C=C) | 1 | 1 | 1.0 |
| N h | 1 | 1 | 1.0 |
| Silicon hydride | 1 | 1 | 1.0 |
| Phenolic | 1 | 1 | 0.7 |
| Aromatic ring | 1 | 1 | 0.7 |
Ranking reflects accumulated literature evidence, not a single authoritative rule. Always confirm against your sample context.
Possible materials
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 2162 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.
Literature behind these assignments
-
Silicon hydride confidence 1.0
“Si-H rock 673 130 Si-H(N 2Si) stretching 2162 92 Si-H(N 3) stretching 2235”
Ay 和 Aydinli - 2004 - Comparative investigation of hydrogen bonding in s DOI: 10.1016/j.optmat.2003.12.004 -
confidence 1.0
“Peak range 2014-2162 due to C=C from alkynes”
Bioprocessing strategies for cost-effective simultaneous removal of chromium and malachite green by marine alga Enteromorpha intestinalis DOI: 10.1038/s41598-020-70251-3 -
confidence 1.0
“A wide band at 2609 reprecm-1 sents stretching vibration of N-H and the presence of a band at 2162 was substituted to CN oscillations.”
Development of Tofacitinib Loaded pH-Responsive Chitosan/Mucin Based Hydrogel Microparticles: In-Vitro Characterization and Toxicological Screening DOI: 10.3390/gels9030187 -
Alkene (C=C) confidence 1.0
“3 2 cm-1 cm-1 at 2161.85 is due to C=C bond vibration [60].”
Prunus armeniaca Gum-Alginate Polymeric Microspheres to Enhance the Bioavailability of Tramadol Hydrochloride: Formulation and Evaluation DOI: 10.3390/pharmaceutics14050916 -
Aromatic ring confidence 0.7
“presence of phenyl, aromatic ring, phenolic compounds confirmed at these ranges”
Synergistic Effects of n-Hexane Fraction of Parkia biglobosa (Jacq.) Bark Extract and Selected Antibiotics on Bacterial Isolates DOI: 10.3390/su9020228
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