What absorbs at 2984 cm⁻¹ in an FTIR spectrum?

Quick answer

A band near 2984 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

A classificação reflete a evidência acumulada da literatura, não uma única regra autoritária. Sempre confirme com o contexto da sua amostra.

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 2984 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

• Alkene (C=C) confiança 1,0

  “cm-1, Characteristic bands of MAA were presented at 1638 4.9 Fourier transform infrared spectroscopy 1700cm-1, 2984cm-1 and on the FTIR spectrum that were associated with C=C stretching vibrations, carboxylic acid groups, C-H and methyl asy”

  Abdullah 等 - 2023 - Formulation of pH-responsive highly swellable hydr DOI: 10.3389/fbioe.2023.1190322
• Alkyl C-H confiança 1,0

  “The FT-IR spectrum of the innovator drug was cm-1 characterized by the principal transmittance bands at 3415 and 3154 due to N-H cm-1 cm-1 (stretching), 3065 due to = C-H (aromatic stretching), 2984 and 2950 due to C-H cm-1”

  Adam 等 - 2022 - Comparative Evaluation of Amlodipine Besylate Gene DOI: 10.14227/DT290422PGC2
• Alkyl C-H confiança 1,0

  “stretching 2984 2 -CH Injection temperature (s) 20 3 3 -CH stretching 2936 Postinjection time (s) 10”

  Cardenas-Trivino 等 - 2019 - Synthesis and Properties of Bionanocomposites of P DOI: 10.1155/2019/4520927
• Alkyl C-H confiança 1,0

  “The FTIR spectrum of FEN showed main absorption bands, significant to C-H stretching of isopropyl group at 2984 cm-1, ester carbonyl stretching at 1725 cm-1, carbonyl stretching at 1648 cm-1, benzene ring stretching at 1597 cm-1, and aryl e”

  Screening of Fenofibrate-Simvastatin Solid Dispersions in the Development of Fixed-Dose Formulations for the Treatment of Lipid Disorders DOI: 10.3390/pharmaceutics15020603
• Hydroxyl (O-H) confiança 1,0

  “The FTIR spectrum of the plant extract shows -1 cm-1 cm-1 characteristics peaks at 3307 for the OH functional group, 2984 for the carboxyl characteristics peaks at 3307 cm-1 for the OH functional group, 2984 cm-1 for the carboxyl”

  Green Synthesis of Silver Nanoparticles Using Rhazya stricta Decne Extracts and Their Anti-Microbial and Anti-Oxidant Activities DOI: 10.3390/cryst13030398
• Alkyl C-H confiança 0,9

  “assigned to stretching vibrations of -CH group”

  Immobilization of Methyltrioxorhenium on Mesoporous Aluminosilicate Materials DOI: 10.3390/ma7042650