What absorbs at 3345 cm⁻¹ in an FTIR spectrum?
A band near 3345 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 5 cited sources
Possible functional-group assignments
| Functional group | Supporting facts | Cited sources | Top confidence |
|---|---|---|---|
| Hydroxyl (O-H) | 3 | 3 | 0.8 |
| N h | 2 | 2 | 1.0 |
Ranking reflects accumulated literature evidence, not a single authoritative rule. Always confirm against your sample context.
Literature behind these assignments
-
N h confidence 1.0
“Explicit assignment in text”
Ahmed 等 - 2023 - Design and Characterization of Baricitinib Incorpo DOI: 10.3390/polym15081825 -
N h confidence 0.9
“shoulder at 3345 cm-1 corresponding to amino insertion”
Brito 等 - 2023 - Influence of Reduction with NaBH4 and HCl in Obtai DOI: 10.3390/polym15132856 -
Hydroxyl (O-H) confidence 0.8
“Listed as one of six distinct OH absorption bands”
Lueder 等 - 2023 - A framework for quantitative in situ evaluation of DOI: 10.5194/ejm-35-243-2023 -
Hydroxyl (O-H) confidence 0.7
“Hydroxyl group peak shift from 3360 to 3305 cm-1, midpoint used.”
Szymanska 等 - 2016 - Preparation and characterization of reactive liqui DOI: 10.1515/polyeng-2014-0393 -
Hydroxyl (O-H) confidence 0.7
“Band at 3345 cm-1 assigned to O-H stretching based on context.”
Machadoa 等 - 2016 - Komagataeibacter rhaeticus as an alternative bacte DOI: 10.1016/j.carbpol.2016.06.049
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