What absorbs at 3736 cm⁻¹ in an FTIR spectrum?

Quick answer

A band near 3736 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.

Mögliche Funktionsgruppenzuweisungen

Das Ranking spiegelt die gesammelte Literatur Evidenz wider, nicht eine einzelne maßgebliche Regel. Bestätigen Sie immer anhand Ihres Probenkontexts.

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 3736 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.

Literatur hinter diesen Zuweisungen

• Silanol (Si-OH) Vertrauen 1,0

  “For cm-1 SiBEA three characteristic bands at 3736, 3705 and 3520 may be attributed to isolated internal, terminal internal and hydrogen-bonded silanol groups, respectively, situated at vacant T-atom sites forming hydroxyl nests [14, 27].”

  High activity of mononuclear copper present in the framework of CuSiBEA zeolites in the selective catalytic reduction of NO with NH3 DOI: 10.1016/j.micromeso.2015.11.065
• Lipid Vertrauen 1,0

  “cm-1, ThePC2loadingplotshowsremarkablepositivevaluespeakingat3736, 3461, 3397 cm-1, 3022sh, 2962, 2926, 2878sh, and 2857 characteristic of lipids.”

  The Role of the Preanalytical Step for Human Saliva Analysis via Vibrational Spectroscopy DOI: 10.3390/metabo13030393
• Alkene (C=C) Vertrauen 1,0

  “Type of vibrations) (cm-1) (cm-1) (cm-1) Stretching vibration Symmetric C=C stretching vibration Stretching vibration of the 3736”

  Hybrid Hosts Based on Sodium Alginate and Porous Clay Heterostructures for Drug Encapsulation DOI: 10.3390/xxxxx
• Hydroxyl (O-H) Vertrauen 1,0

  “of the cm-1 Vibration Peak position, vibration assignments Hydrogen chloride H-Cl asymmetric stretching 3150-2600 Saturated hydrocarbon C-H stretching 2935 Plasticizer (ester group) C-O-C symmetric stretching 1120 C-O-C asymmetric stretchin”

  Zhao 等 - 2022 - Experimental investigation and numerical modeling DOI: 10.1007/s10973-022-11723-8
• Hydroxyl (O-H) Vertrauen 0,8

  “Text: 'the most intense bands at 3736 and 3745 ... groups and isolated external groups'”

  Engineering the porosity and acidity of H-Beta zeolite by dealumination for the production of 2-ethylanthraquinone via 2-(4′-ethylbenzoyl)benzoic acid dehydration DOI: 10.1039/c7ra13576a