What absorbs at 2270 cm⁻¹ in an FTIR spectrum?
A band near 2270 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
Possible functional-group assignments
| Functional group | Supporting facts | Cited sources | Top confidence |
|---|---|---|---|
| N c o | 12 | 11 | 0.95 |
| Isocyanate | 6 | 5 | 1.0 |
| Amide | 1 | 1 | 0.8 |
Ranking reflects accumulated literature evidence, not a single authoritative rule. Always confirm against your sample context.
Literature behind these assignments
-
Isocyanate confidence 1.0
“Explicit assignment in text.”
Cateto 等 - 2008 - Monitoring of lignin-based polyurethane synthesis DOI: 10.1016/j.indcrop.2007.07.018 -
confidence 0.95
“Explicit assignment: 'disappearance of the isocynate absorption peak'”
Kang - 2014 - Concentration effect on the optical absorption and DOI: 10.1117/12.2061447 -
N c o confidence 0.95
“Text: 'The NCO absorption peak at about 2270 disappeared'”
Wang 和 Jin - 2018 - Preparation and Characterization of Self-Colored W DOI: 10.3390/polym10030289 -
Isocyanate confidence 0.95
“Band at 2270 cm-1 characteristic for isocyanate group; disappearance confirms reaction completeness.”
Slobodinyuk 等 - 2022 - Preparation, Structure and Properties of Urethane- DOI: 10.3390/polym14030524 -
N c o confidence 0.9
“Peak at 2270 cm-1 indicates NCO.”
Bonakdar 等 - 2010 - Preparation and characterization of polyvinyl alco DOI: 10.1016/j.msec.2010.02.017 -
Isocyanate confidence 0.9
“Explicit assignment in text.”
Fu 和 Fan - 2016 - Curing reaction kinetics of HTPE polymer studied b DOI: 10.1007/s10973-016-5485-8 -
Isocyanate confidence 0.9
“Text: 'characteristic isocyanate absorption peak at 2270'”
Kim 和 Kang - 2012 - Optical properties of azo-chromophore attached on DOI: 10.1117/12.999810 -
confidence 0.9
“Explicit assignment: 'FTIR absorption peak at 2270 cm-1 representing asymmetric stretching'.”
Kim 和 Kang - 2014 - Fluorescence resonance energy transfer of sulforho DOI: 10.1016/j.matchemphys.2014.09.006
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