What absorbs at 1181 cm⁻¹ in an FTIR spectrum?

Quick answer

A band near 1181 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.

Possibili assegnazioni di gruppi funzionali

La classifica riflette le prove bibliografiche accumulate, non una singola regola autorevole. Conferma sempre nel contesto del tuo campione.

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 1181 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.

Letteratura dietro queste assegnazioni

• C c single bond affidabilità 1,0

  “carbon).37a,b stretching, where the apex denotes a chain bance-frequency spectrum, when the data are collected cm-1 cm-1 A peak at 1181 has contributions from aromatic at a nominal resolution of 4 (see Figure 2 and C-C¢ C-H in-plane bending”

  Musto 等 - 2005 - Host-guest interactions and crystalline structure DOI: 10.1021/ma0477899
• Acetate affidabilità 1,0

  “Figure 8(b) shows that the peaks observed at 1064 maycorrespondto-C-O-C-,whilepeaksobservedbetween1181.33cm(cid:6)1 binding density that characterizes the number of non-electronic-sharing cm(cid:6)1 C-O interactions between atoms such as io”

  Optical characterizations of PMMA/metal oxide nanoparticles thin films: bandgap engineering using a novel derived model DOI: 10.1016/j.heliyon.2021.e05952
• Oxygen heterocycle affidabilità 1,0

  “The decrease of the absorption band near 1181 cm-1, which was derived from the bridge between the benzene rings [40], indicates that the backbone chains of epoxy resin can be cut by thermal aging.”

  Reinforced Structure Effect on Thermo-Oxidative Stability of Polymer-Matrix Composites: 2-D Plain Woven Composites and 2.5-D Angle-Interlock Woven Composites DOI: 10.3390/polym14173454
• Hydroxyl (O-H) affidabilità 1,0

  “0.6 3523cm-1 3000 , O-H deformation vibrastretching vibration at 1441cm-1 1181cm-1 tion at”

  Li 和 Yang - 2014 - Fabrication and Characterization of Electrospun Wo DOI: 10.1155/2014/163678
• affidabilità 1,0

  “cm-1 2847 cm-1 due to the alkyl groups, a peak at 1648 cm-1 related to the N-H bending belonging to -NH2 2847 due to the alkyl groups, a peak at 1648 related to the N-H bending belonging to -NH 2 cm-1 groups, and peaks at around 1181 and 10”

  Acrylic Pressure-Sensitive Adhesive Reinforced with Aluminum Nitride and Its Thermal Properties: Effect of Surface Treatment and Particle Size DOI: 10.3390/coatings10020188
• Acetate affidabilità 1,0

  “1181 which is the C-O stretching in -CH-O and micro (< 2 mm) residues.”

  Degradation of Film and Rigid Bioplastics During the Thermophilic Phase and the Maturation Phase of Simulated Composting DOI: 10.1007/s10924-021-02098-2
• Acetate affidabilità 1,0

  “cm-1 cm-1, cm-1, In addition, the most significant absorptions are observed at 1737 and 1092 1181 cm-1 1274 corresponding to the C=O and C-O-C respectively [12], indicating the existence of ester 1H group.”

  Wen 等 - 2018 - A novel oligomer containing DOPO and ferrocene gro DOI: 10.1016/j.polymdegradstab.2018.08.010
• Acetate affidabilità 1,0

  “The absorption peak at 1181 was the anti-symmetric stretching of the C-O-C of the ester substance [47].”

  Nano Catalysis of Biofuels and Biochemicals from Cotinus coggygria Scop. Wood for Bio-Oil Raw Material DOI: 10.3390/polym14214610