What absorbs at 2985 cm⁻¹ in an FTIR spectrum?
A band near 2985 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 7 cited sources
Possible functional-group assignments
| Functional group | Supporting facts | Cited sources | Top confidence |
|---|---|---|---|
| Alkyl C-H | 5 | 5 | 1.0 |
| Amide | 1 | 1 | 1.0 |
| Methyl | 1 | 1 | 1.0 |
| Methoxy (OCH3) | 1 | 1 | 1.0 |
| Methacrylate | 1 | 1 | 1.0 |
| Acetate | 1 | 1 | 1.0 |
| Hydroxyl (O-H) | 1 | 1 | 1.0 |
| Carbohydrate | 1 | 1 | 1.0 |
Ranking reflects accumulated literature evidence, not a single authoritative rule. Always confirm against your sample context.
Literature behind these assignments
-
Carbohydrate confidence 1.0
“The band at 2985 could be ascribed to the symmetric vibration of cellulose oxygen-hydrogen (O-H) groups.”
Physical and Chemical Characteristics of Agricultural-Plastic Wastes for Feasibility of Solid Fuel Briquette Production DOI: 10.3390/su142315751 -
Alkyl C-H confidence 1.0
“by T he U 2990 2990 CH symmetric vibrations 2985 [19] α PVDF niversity 2 O 3025 3025 CH antisymmetric vibrations 3023 [19] α PVDF”
Chipara 等 - 2020 - Spectroscopic investigations on PVDF-Fe2O3 nanocom DOI: 10.1002/app.48907 -
Acetate confidence 1.0
“- 3200-3400 N-H Stretching 3315 - - 3324 3324 3324 3324 and CH3 Stretching 2985, 2936 2900 2870-2950 2850, 2870, 2850, 2870, 2850, 2870, 3000-2800 CH2”
El-Shekeil 等 - 2012 - Effect of pMDI isocyanate additive on mechanical a DOI: 10.1177/0021998310385030) -
Alkyl C-H confidence 1.0
“metric stretching bands respectively at 2875 and glues It should be noticed that these CH stretching bands appear ]OH 3570 better resolved in the spectrum of casein, with CH3 groups ] 3370 asNH of greater intensity than CH2 groups, whereas”
Invernizzi 等 - 2018 - Mid and Near-Infrared Reflection Spectral Database DOI: 10.1155/2018/7823248 -
Alkyl C-H confidence 1.0
“3190 C-H (aliphatic) Stretching 2985 2985 2951”
Merline 等 - 2013 - Melamine formaldehyde curing studies and reaction DOI: 10.1038/pj.2012.162; -
Alkyl C-H confidence 1.0
“LLM confirmed rule peak-group candidate”
Tran 等 - 2022 - Depolymerization of Rice Straw Lignin into Value-A DOI: 10.1155/2022/7872307 -
confidence 0.9
“Same sentence as 1109.”
Study on Thermal Decomposition Behaviors of Terpolymers of Carbon Dioxide, Propylene Oxide, and Cyclohexene Oxide DOI: 10.3390/ijms19123723
Have a spectrum with this band?
Upload your FTIR spectrum and get a full interpretation report — peak assignments with literature citations, library matches, and a confidence-rated evidence chain — in seconds.
Interpret my spectrum