What absorbs at 1081 cm⁻¹ in an FTIR spectrum?

Quick answer

A band near 1081 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 1081 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

• Hydroxyl (O-H) confidence 1.0

  “One strong (1658 amide I), one medium (3346 H-O-H stretchcm-1: cm-1: ing), and 2 weak (1156 urea and 1081 Glycosylated proteins) peaks were observed in the phase II cm-1 spectra of urine samples (Fig.”

  Analysis of the ex-vivo transformation of semen, saliva and urine as they dry out using ATR-FTIR spectroscopy and chemometric approach DOI: 10.1038/s41598-021-91009-5
• Acetate confidence 1.0

  “Moreover, the weak adsorption band at 1081.34 is related to symmetric stretching in cm(cid:0) 1 P-CH3 the urethane group [3,37,61,79,83].”

  Biologically-induced synthetic manganese carbonate precipitate (BISMCP) for potential applications in heavy metal removal DOI: 10.1016/j.heliyon.2023.e15919
• Acetate confidence 1.0

  “The characteristic peaks at 3287.49 (-OH stretching), cm-1 cm-1 cm-1 2917.48 (-CH stretching vibration), 1080.55 (-C-O stretching vibration), 1421.57 cm-1 (symmetrical -CH deformation mode).”

  Sprayed in-situ synthesis of Polyvinyl alcohol/Chitosan loaded Silver nanocomposite hydrogel for improved antibacterial effects DOI: 10.1016/j.ijbiomac.2019.09.186
• Acetate confidence 1.0

  “There is more separation between the A cm-1) u peaks arising from C-C and C-O vibrations (~1081 and the Fe-O-P peak (~1040 t h cm-1), α-FeOOH.”

  Parikh 等 - 2014 - ATR-FTIR spectroscopic evidence for biomolecular p DOI: 10.1016/j.colsurfb.2014.04.022.
• Phosphate (PO4) confidence 1.0

  “In accordance with selection rules, the triply degenerate antisymmetric 1081 1081 1081 1080 stretching and bending modes (F2) are both Raman and infrared active, whereas the non-degenerate ν (P-O) 1063 1062 1062 1064 3 symmetric stretching”

  New Ca2.90(Me2+)0.10(PO4)2 -tricalcium Phosphates with Me2+ = Mn, Ni, Cu: Synthesis, Crystal-Chemistry, and Luminescence Properties DOI: 10.3390/cryst9060288
• Thiol confidence 1.0

  “± stretch),576.19(C-Sstretch),707.35(C-Sstretch),1080.53(S-H (1 mg/mL), 13.000 2.887 (0.1 mg/mL), 29.667 1.453 ± ± stretch), 1152.55 (CN stretch), 1240.62 (aryl-O stretch), 1459.01 (10 mg/mL), 19.000 1.000 (1 mg/mL), and 8.000 00.000 = (aro”

  Ao 等 - 2022 - Green synthesis of biogenetic Te(0) nanoparticles DOI: 10.3389/fmicb.2022.1020179
• Acetate confidence 1.0

  “Furthermore, the cm-1 band at 1081 and 1025 is assigned for the stretching of C-O-C group, however, C-C-H stretching, C-O-C glycosidic linkage (ring breathing), and -C-C (C-C-O ring) could be associated with the peak of 949, 887, and 814 cm”

  Faried 等 - 2017 - Green Synthesis of Silver Nanoparticles in Biopoly DOI: 10.1063/1.4968377
• Acetate confidence 1.0

  “In T cm-1, which are the tablets shows peaks at 3400 relaxation, no energy is transferred from the nuclei cm-1 attributed to the O-H stretching of TS, at 1158 to their surroundings and the process is an entropycm-1, which are associated to”

  Fernandes 等 - 2019 - The development and characterization of Propranolo DOI: 10.1590/0001-3765201920180094