What absorbs at 636 cm⁻¹ in an FTIR spectrum?

Quick answer

A band near 636 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.

Attributions possibles de groupes fonctionnels

Le classement reflète les preuves bibliographiques accumulées, et non une règle faisant autorité. Confirmez toujours dans le contexte de votre échantillon.

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 636 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.

Bibliographie derrière ces attributions

• confiance 1,0

  “additional Raman bands of C-Cl vibrations in the lower wavenumber region at 636 and 695 The bands cm-1 cm-1 around 1302 and 1437 were assigned to the methylene groups.”

  Optical photothermal infrared spectroscopy with simultaneously acquired Raman spectroscopy for two-dimensional microplastic identification DOI: 10.1038/s41598-022-23318-2
• Fluorine (C-F) confiance 1,0

  “Minor bands at 636 and cm(cid:5)1 553 were observed and are assigned to the CF2 wagging and CF2 deformation modes, respectively.”

  In vitro mineralisation of grafted ePTFE membranes carrying carboxylate groups DOI: 10.1016/j.bioactmat.2017.02.002
• Metal oxygen confiance 1,0

  “The region at 1107 9 cm1 is attributed to the absorption peak at 1467 antisymmetric stretching vibrations of the BO group, 3 m1 m1 and 484 are ascribed to the vibrations and 636 of the AlO polyhedral and lattice vibrations contained x 2θ”

  Wang 等 - 2015 - A facile method to fabricate Al4B2O9 whiskers on p DOI: 10.1007/s40145-015-0154-0
• Sulfonate confiance 1,0

  “2 for the region between 1800 to 600 The band 636 attributed to of BMIMCF 2 3 0 2 3 symmetric deformation of the salt remained unshifted as concentration of BMIMCF 3SO added is increased SO 3 3”

  Zulkepeli 等 - 2017 - Infrared Studies of PVC-based Electrolytes Incorpo DOI: 10.1063/1.4999880
• Metal oxygen confiance 0,9

  “band shift from 636.27 to 587.25 on MmGO”

  Adsorptive and photocatalytic activity of Fe3O4-functionalized multilayer graphene oxide in the treatment of industrial textile wastewater DOI: 10.1007/s11356-020-10926-6
• C c single bond confiance 0,7

  “Text: 'The peaks at 636, cm¡1' followed by 'C-C bending modes of adsorbed water and stretching vibration'.”

  Synthesized and magnetic and ferroelectric phase transitions of single phase multiferroic YMn2O5 nanoparticles through microwave assisted polyacrylamide gel method DOI: 10.1080/00150193.2017.1375302
• confiance 0,7

  “Raman mode Eg of anatase.”

  Zhao 和 Tay - 2006 - Study of nanocrystal TiO2 thin films by thermal an DOI: 10.1007/s10832-006-9903-3