What absorbs at 1013 cm⁻¹ in an FTIR spectrum?
A band near 1013 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 1013 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 |
|---|---|---|---|
| Methacrylate | 5 | 4 | 1.0 |
| Acetate | 5 | 4 | 1.0 |
| Methoxy (OCH3) | 4 | 3 | 1.0 |
| C-O single bond | 4 | 3 | 1.0 |
| Alkyl C-H | 3 | 3 | 1.0 |
| Silicon (Si) | 2 | 2 | 1.0 |
| Carboxyl (COOH) | 2 | 2 | 1.0 |
| Carbonyl (C=O) | 2 | 2 | 1.0 |
| Amide | 2 | 2 | 1.0 |
| Phosphate (PO4) | 2 | 2 | 1.0 |
| Siloxane (Si-O-Si) | 1 | 1 | 1.0 |
| Silicon-oxygen (Si-O) | 1 | 1 | 1.0 |
| Ketone | 1 | 1 | 1.0 |
| Ester | 1 | 1 | 1.0 |
| Alkene (C=C) | 1 | 1 | 1.0 |
| Water (H2O) | 1 | 1 | 1.0 |
| Phosphorus | 1 | 1 | 1.0 |
| Metal oxygen | 1 | 1 | 1.0 |
| C c single bond | 1 | 1 | 1.0 |
| Adsorbed carbon monoxide | 1 | 0 | 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 |
|---|---|---|---|
| chitosan | 1013, 1650, 1655 | Acetate, Methacrylate, C-O single bond | 1 |
| polypyrrole | 1013, 1700, 400 | Methacrylate, Acetate | 1 |
| polysaccharide | 1013, 1637, 1320 | Methacrylate, Acetate, C-O single bond | 1 |
| collagen | 1013, 1408, 1660 | Methacrylate, Acetate, Methoxy (OCH3) | 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 1013 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
-
C c single bond confidence 1.0
“The cm-1 intense band observed at 1421 and 1382 are corresponds to stretching vibrations of C=O cm-1 and the band at ~ 1013 is due to the C-C bonding [51].”
Hydrothermal synthesis of surfactant assisted Zn doped SnO2 nanoparticles with enhanced photocatalytic performance and energy storage performance DOI: 10.1016/j.jpcs.2020.109407 -
Phosphate (PO4) confidence 1.0
“of PTA peaked at 1013 cm-1 and 989 cm-1 and were assined to the vbirational modes of the another two Raman lines of low intensity at 523 and 218-237 The Raman lines cm-1 cm-1 of PTA peaked at 1013 and 989 and were assined to the vbirational”
The Photoluminescence and Vibrational Properties of Black Phosphorous Sheets Chemically/Electrochemically Functionalized in the Presence of Diphenylamine DOI: 10.3390/polym14214479 -
Acetate confidence 1.0
“cm-1) corresponding to the replacement of OH groups by NH2 groups on shoulder (3345 cm-1, cm-1,and cm-1 the surface of CG [8].We can also identify bands at 1132 1078 1013 cm-1, 1078 cm-1,and 1013 cm-1 the surface of CG [8].We can also ident”
Influence of Reduction with NaBH4 and HCl in Obtaining Amino Derivatives of Cashew Gum and Cytotoxic Profile DOI: 10.3390/polym15132856 -
Alkyl C-H confidence 1.0
“25 of isolated anion 2943/- -/- 2937/- 27-C 25-H 2-N 1-C stretch/C-H -/1013 symm H 1023/1013 1025/1011 C”
Dhumal 等 - 2016 - Molecular Interactions of a Cu-Based Metal-Organic DOI: 10.1021/acs.jpcc.5b10123 -
Alkyl C-H confidence 1.0
“The C-H band in pyrrole appeared at1013cm-1andwasslightlyshiftedtowardsthelowerregion research reported by Wei et al.”
Diauudin 等 - 2020 - Preparation and Characterisation of Polypyrrole-Ir DOI: 10.1155/2020/8762969 -
Amide confidence 1.0
“FTIR spectroscopy measurements indicated the formation of the cm-1 cm-1 scaffold-the amide I and amide II bands between 1013 and 1033 were clearly visible, indicating the presence of C-O stretching (C-O-C).”
Application of Vibrational Spectroscopic Techniques in the Study of the Natural Polysaccharides and Their Cross-Linking Process DOI: 10.3390/ijms24032630 -
Phosphate (PO4) confidence 1.0
“4 For example, measurements perpendicular to c-axis can cm-1 cm-1, result in a phosphate band at ~ 1013 to ~ 1016”
Hammerli 等 - 2021 - Measuring in situ CO2 and H2O in apatite via ATR-F DOI: 10.1007/s00410-021-01858-6 -
Water (H2O) confidence 1.0
“In addition to its large surface area (due to a well-connected pore network structure), the collagen scaffold with elastin exhibited higher crosslinking efficiency (from 74.70% to 88.77%), higher water absorption (from 1012.70% to 1799.06%)”
Functionalised Hybrid Collagen-Elastin for Acellular Cutaneous Substitute Applications DOI: 10.3390/polym15081929
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