What absorbs at 760 cm⁻¹ in an FTIR spectrum?

Quick answer

A band near 760 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.

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 760 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

• confidence 1.0

  “bands at 480 to 750 (M-O stretching) with Ag 2O at 580 while ZrO 2-Ag 2O samples showed bands at 760 The screening by agar diffusion assay revealed a pronounced increase in the antibacterial activity of ZrO 2-Ag 2O against all the tested ba”

  Ayanwale 等 - 2020 - Bactericidal Activity Study of ZrO2-Ag2O Nanoparti DOI: 10.1177/1559325820941374
• Carbonate confidence 1.0

  “cm-1 thetic carbonated apatites, we found that the carbonate spectra have been to either a single band at 750-760 cm-1 content of the bone sample was 7.7 ± 0.4%.”

  Awonusi 等 - 2007 - Carbonate assignment and calibration in the raman DOI: 10.1007/s00223-007-9034-0
• Alkyl C-H confidence 1.0

  “LLM confirmed rule peak-group candidate”

  Kumar 和 Rao - 2018 - Structural and electrochemical properties of PVP-C DOI: 10.1088/2053-1591/aace40
• Nitrogen heterocycle confidence 1.0

  “two terminal vinyl characteristic frequency, and a peak of Samples cm-1 760 is attributed to the bending vibration of outer cm-1 surface of the imidazole ring CH.”

  Thermal stability and lifetime of [AMIM]Cl-PFSA composite membranes DOI: 10.1007/s10973-016-6065-7
• Water (H2O) confidence 1.0

  “shows that the band at 760 Nanorings 2 cm-1 is due to the presence of water molecules between the Raman spectrum shows that the band at 264 Nanorods μm layers.”

  Nagaraju 等 - 2012 - Na0.33V2O5 center dot 1.5H(2)O nanoringsnanorods DOI: 10.1016/j.ssi.2012.08.014
• Hydroxyl (O-H) confidence 1.0

  “cm-1 Ti-OH TAl vibrations.[26] indicating > 0.5 apfu, and that at ~580 to Such an breathing mode is >19 cm-1, indiand no pronounced peak is observed near 760 assignment is however doubtful, because most if not all WO2Ti-OH CTi CTi associate”

  Nondestructive determination of the amphibole crystal‐chemical formulae by Raman spectroscopy: One step closer DOI: 10.1002/jrs.5626
• Aromatic ring confidence 1.0

  “The strong sharp bands at 760 cm-1, 793 cm-1, and 822 cm-1 can be ascribed cm-1 cm-1, to o-disubstituted benzene ring vibration [38].”

  Synthesis, Characterization and Biological Activities of New Schiff Base Compound and Its Lanthanide Complexes DOI: 10.3390/ph15040454
• Alkyl C-H confidence 1.0

  “The sharp peaks at 760 cm-1 were attributed to bending C-H benzene derivatives.”

  Bio-Fabrication of ZnONPs from Alkalescent Nucleoside Antibiotic to Control Rice Blast: Impact on Pathogen (Magnaporthe grisea) and Host (Rice) DOI: 10.3390/ijms24032778