What absorbs at 1583 cm⁻¹ in an FTIR spectrum?

Quick answer

A band near 1583 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 1583 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-oxygen (Si-O) confidence 1.0

  “FTIR spectra of SiO2(RHA)-Arg shows two new peaks at 1672 and 1583 cm-1 confirming NH2 and C=O groups, respectively.”

  Hastuti 等 - 2019 - Synthesis and characterization of L-Arginine modif DOI: 10.1088/1757-899X/509/1/012135
• C=n confidence 1.0

  “cm-1 cm-1 C=N, assigned to the carbonyl group, one band at 1583 was assigned to and one band at 742 belonging to the C-N bond.”

  Synthesis of Nylon 6/Modified Carbon Black Nanocomposites for Application in Uric Acid Adsorption DOI: 10.3390/ma13225173
• Carboxyl (COOH) confidence 1.0

  “cm-1, 1400, 1305, 1066, and 756 Hydroxyl groups were attributed to the band 3260 spectrum for leaf extract, the major stretching frequencies were observed at 3260, 2096, whereas carbonyl stretching vibrations and asymmetric carboxylate stre”

  Green Synthesis of TiO2 Nanoparticles Using Acorus calamus Leaf Extract and Evaluating Its Photocatalytic and In Vitro Antimicrobial Activity DOI: 10.3390/catal12020181
• Ring structure confidence 1.0

  “After this treatment, the band which corresponds to Py ring stretching vibration is cm-1 shifted to 1583 and tosylate bands have disappeared (Fig.”

  New conductive copolymer membranes via track-etched PC templates for biological media ultra-filtration DOI: 10.1016/j.nimb.2007.08.066
• Carboxyl (COOH) confidence 1.0

  “This was also confirmed by the differences in spectrum bands: the peak shift to 1583 cm-1 (corresponding to the asymmetric and symmetric stretching of -COOassociated with carboxylic acid salts) and the significant increase in the peak inten”

  Novel Mixed Matrix Sodium Alginate–Fullerenol Membranes: Development, Characterization, and Study in Pervaporation Dehydration of Isopropanol DOI: 10.3390/polym12040864
• Amide confidence 1.0

  “cm-1 In the FTIR spectra of AuPEG 2000-TAT-DOX, iAuPEG 2000-TAT-DOX the bands at 1676 (amide I), 1583 cm-1 (amide II) and 1392 (amide III) or 1668, 1587 and 1392 respectively are well resolved with their intensity higher than 1, meaning the”

  Effect of TAT-DOX-PEG irradiated gold nanoparticles conjugates on human osteosarcoma cells DOI: 10.1038/s41598-020-63245-8
• Ring structure confidence 1.0

  “1650a, 1651b, 1655c 1,648 -NH2 scissoring, C6-NH2 stretching 1598a, 1602b, 1606cd 1,605 Purine ring vibration, -NH2 scissoring, N3-C4 stretching 1583a, 1580b, 1576c 1,579 Purine ring vibration, six membered ring deformation (C5-C6 stretchin”

  Rakshit 等 - 2022 - Influence of Citrate and Phosphate on the Adsorpti DOI: 10.3389/fenvs.2022.894581
• Ring structure confidence 1.0

  “protonated water clusters [15], while the latter, observed here at 1583 on the GO dehydrated protonated water clusters [15], while the latter, observed here at 1583 cm-1 on the GO dehydrated 2 h ◦ νC=C νC=C 2 h at 150 C, was attributed as w”

  Acid Properties of GO and Reduced GO as Determined by Microcalorimetry, FTIR, and Kinetics of Cellulose Hydrolysis-Hydrogenolysis DOI: 10.3390/catal10121393