What absorbs at 959 cm⁻¹ in an FTIR spectrum?
A band near 959 cm⁻¹ can point to several functional groups. Below are the most likely assignments, ranked by how much published evidence supports each — every one traceable to literature (DOI) and cross-validated against our 130,000+ reference spectra and knowledge graph.
Backed by 8 cited sources
Quick answer
A band near 959 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
| Functional group | Supporting facts | Cited sources | Top confidence |
|---|---|---|---|
| Phosphate (PO4) | 6 | 6 | 1.0 |
| Alkyl C-H | 3 | 3 | 1.0 |
| Chlorine | 2 | 2 | 1.0 |
| Phosphorus | 2 | 2 | 1.0 |
| Lignin | 1 | 1 | 1.0 |
| Hydroxyl (O-H) | 1 | 1 | 1.0 |
| Methoxy (OCH3) | 1 | 1 | 1.0 |
| Methacrylate | 1 | 1 | 1.0 |
| C-O single bond | 1 | 1 | 1.0 |
| Acetate | 1 | 1 | 1.0 |
| Alkene (C=C) | 1 | 1 | 1.0 |
| Silicon-oxygen (Si-O) | 1 | 1 | 1.0 |
| Silicon (Si) | 1 | 1 | 1.0 |
| Carbonate | 1 | 1 | 1.0 |
Ranking reflects accumulated literature evidence, not a single fixed rule. Always confirm against your sample context.
Possible materials
| Material | Supporting peaks | Overlapping groups | Cited sources |
|---|---|---|---|
| PVC | 959, 834, 1195 | Alkyl C-H, Chlorine | 2 |
| PMMA | 959, 1722, 1383 | Alkyl C-H | 1 |
| SiO2 | 959, 1739, 699 | Alkyl C-H | 1 |
| zinc oxide | 959, 1627, 1638 | Alkyl C-H | 1 |
| zinc oxide nanoparticles | 959, 1744, 1627 | Alkyl C-H | 1 |
| hydroxyapatite | 959, 1620, 1639 | Phosphate (PO4), Alkyl C-H, Phosphorus | 1 |
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 959 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
-
Phosphate (PO4) confidence 1.0
“The predominate peak at cm-1 reflection (ATR)/Fourier transform 959 due to the stretching mode infrared (FTIR) and confocal Raman of phosphate was also found in the microspectroscopies were used to Raman spectrum of corneal calcified Taipei”
Chen 等 - 2006 - Corneal calcification chemical composition of cal DOI: 10.1007/s00417-005-1191-0 -
Phosphate (PO4) confidence 1.0
“The black line cm-1 ((cid:2) ((cid:2) 959 phosphate stretching) and 873 carbonate mode) displays pixel locations from which the single pixel IR spectra 1 2 displayed in Fig.”
Chiou 等 - 2011 - FT-IR microscopic imaging of calcified deposit of DOI: 10.1016/j.vibspec.2011.06.004 -
Silicon (Si) confidence 1.0
“The peak at 959 and 781 assigned modified and surface modified ZnO nanoparticles, the Contact angle for Si-O bonding in VTES has disappear in VTES modified ZnO nano-”
Surface modification of zinc oxide nanoparticles by vinyltriethoxy silane (VTES) DOI: 10.1016/j.inoche.2020.108347 -
confidence 1.0
“1 FTIR spectra of a LiCF 3SO 3, b PVC, and c PVC:LiCF 3SO (50:50) system 3 15:413-420 Ionics (2009) 415 C-H and wave numbers exhibited by PVC are stretching cm-1, mode observed at 2,911 CH deformation mode at 2 cm-1, cm-1, C-H trans C-H 1,3”
Ramesh 和 Yi - 2009 - FTIR spectra of plasticized high molecular weight DOI: 10.1007/s11581-008-0279-z -
Alkyl C-H confidence 1.0
“For PVC, C H stretching mode can be S.Rameshetal./SpectrochimicaActaPartA66(2007)1237-1242 1239 Table2 VibrationalmodesandwavenumbersexhibitedbyPMMA Wavenumbers(cm-1) Descriptionofvibrations References C Hstretching 2927-2986 [30,32] C Ostr”
Ramesh 等 - 2007 - FTIR studies of PVCPMMA blend based polymer elect DOI: 10.1016/j.saa.2006.06.012 -
Alkyl C-H confidence 1.0
“Additionally, lycopene spectra presented characteristic bands at cm-1 cm-1, 959 or 960 indicating a characteristic of out-of-plane C-H bending mode for a trans-conjugated alkene [2,28].”
Bio-Availability, Anticancer Potential, and Chemical Data of Lycopene: An Overview and Technological Prospecting DOI: 10.3390/antiox11020360 -
Phosphate (PO4) confidence 1.0
“Moreover, the spectrum of pure HAp shows an intense doublet at 1087-1020 cm-1 pertinent to asymmetric stretching (ν3) and a weak peak at 959 cm-1 (Table 5) that can be assigned to the symmetric stretching mode of the [PO 4]3group [54] (Tabl”
Structural Characterization of Low-Sr-Doped Hydroxyapatite Obtained by Solid-State Synthesis DOI: 10.3390/cryst13010117 -
Phosphate (PO4) confidence 1.0
“LLM confirmed rule peak-group candidate”
Jabin 等 - 2021 - Quantitative Analysis and Effect of SDF, APF, NaF DOI: 10.5005/jp-journals-10005-1988
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