What absorbs at 2825 cm⁻¹ in an FTIR spectrum?

Quick answer

A band near 2825 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.

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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 2825 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.

Literatūra aiz šiem piešķīrumiem

• pārliecība 1,0

  “cm-1 The band centered at 2825 corresponds to N-H stretching vibration [27].”

  Synthesis of novel conducting polyaniline composites based on seaweed Enteromorpha compressa macro-alga powder DOI: 10.1007/s00289-020-03191-7
• Alkyl C-H pārliecība 1,0

  “These results correlate with the already around 3390 and -CH stretching around 2825 reported results in which similar peaks have been observed are responsible for strong capping on the ZnO nanoparti-”

  Biosynthesis of zinc oxide nanoparticles using leaf extract of Calotropis gigantea: characterization and its evaluation on tree seedling growth in nursery stage DOI: 10.1007/s13204-017-0586-7
• C-O single bond pārliecība 1,0

  “However, a new peak at 2825 is appeared and assigned to the stretching of OCH that exists in methyl sulfate.”

  An appraisal of the thermal decomposition mechanisms of ILs as potential lubricants DOI: 10.1002/ls.1457
• Alkyl C-H pārliecība 1,0

  “LLM confirmed rule peak-group candidate”

  Wang 等 - 2014 - Electrospun polyurethane-core and gelatin-shell co DOI: 10.1088/1758-5082/6/1/015002.
• Alkyl C-H pārliecība 1,0

  “FTIR spectra of unoxidized coal in this region have seven tted peaks, namely CH symmetric stretching 2 cm1), cm1), vibration (2825 and 2849 CH symmetric stretching vibration (2872 and 2895 and the 3 cm1)”

  Wang 等 - 2023 - Study on the thermal kinetics and microscopic char DOI: 10.21203/rs.3.rs-2868841/v1