What absorbs at 1541 cm⁻¹ in an FTIR spectrum?

Quick answer

A band near 1541 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

Ranking reflects accumulated literature evidence, not a single fixed 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 1541 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

• Amide confidence 1.0

  “LLM confirmed rule peak-group candidate”

  Change of chemical composition and hydrogen bonding behavior due to chlorination of crosslinked polyamide membranes DOI: 10.1002/app.25657
• Acetate confidence 1.0

  “Initially, the spectrum of the aggregate contained a peak at cm-1 1541 perhaps due to an intermediate acetate-containing Figure 3.”

  MacDonald 等 - 2016 - Reaction of Pb(II) and Zn(II) with Ethyl Linoleate DOI: 10.1021/acsomega.6b00075
• Amide confidence 1.0

  “eliminated as indicated by the absence of the amide peaks at 1541cm(cid:3)1 peaksat3172(broad),1953,and1578cm(cid:3)1whilethe(cid:3)2.5ppm and the imide 3314, 3259, 2079(broad), 1567, and peak remained upon reanalysis by NMR.”

  Mills 等 - 2009 - Commercializable power source from forming new sta DOI: 10.1016/j.ijhydene.2008.10.018
• Hydroxyl (O-H) confidence 1.0

  “transmittance peak at band 1541.28 The presence of several functional groups including -OH stretch and -NH stretch on commercial activated carbon has improved CO binding process onto the 2 surface of activated carbon [13].”

  Raman 等 - 2017 - Preparation and Characterization of Impregnated Co DOI: 10.1088/1757-899X/206/1/012005
• Amide confidence 1.0

  “The peaks at 1541 and cm1 1236 are assigned to the amide II and amide III bands of protein, respectively.”

  Preparation, Characterization and Antibacterial Evaluation of Soy Protein Isolate Biopolymeric Films Loaded with Nalidixic Acid DOI: 10.1007/s10924-020-01729-4
• Amide confidence 1.0

  “LLM confirmed rule peak-group candidate”

  Tang 等 - 2009 - Effect of membrane chemistry and coating layer on DOI: 10.1016/j.desal.2008.04
• Amide confidence 1.0

  “LLM confirmed rule peak-group candidate”

  Van 等 - 2012 - Degradation of Polyamide Nanofiltration and Revers DOI: 10.1021/es203090y
• Alkene (C=C) confidence 1.0

  “As expected, the PP-ZnONFs showed a high SSA m2/g cm-1 weak band at 1541 of 19.61 which was almost 6 times higher than that corresponded to C=C stretching m2/g) of commercial ZnO nanoparticles (3.23 (Chakrabarti bonds of aromatic compounds”

  Synthesis of photocatalytic zinc oxide nanoflowers using Peltophorum pterocarpum pod extract and their characterization DOI: 10.1007/s13204-021-01919-z