What absorbs at 750 cm⁻¹ in an FTIR spectrum?
A band near 750 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 |
|---|---|---|---|
| Boron nitrogen | 2 | 2 | 0.95 |
| Metal oxygen | 2 | 2 | 0.7 |
| Oxygen heterocycle | 2 | 0 | 0.9 |
| Sulfur heterocycle | 1 | 1 | 1.0 |
| C n single bond | 1 | 1 | 0.9 |
| Carbon dioxide | 1 | 1 | 0.9 |
| C-O single bond | 1 | 1 | 0.9 |
| Aromatic ring | 1 | 1 | 0.8 |
| N h | 1 | 1 | 0.8 |
| Water (H2O) | 1 | 0 | 0.9 |
| Hydroxyl (O-H) | 1 | 0 | 0.9 |
| Carboxyl (COOH) | 1 | 0 | 0.5 |
Ranking reflects accumulated literature evidence, not a single authoritative rule. Always confirm against your sample context.
Literature behind these assignments
-
Sulfur heterocycle confidence 1.0
“Belong to thiophene ring vibrations.”
Refat 等 - 2021 - SYNTHESIS, CHARACTERIZATION, THERMAL ANALYSIS AND DOI: 10.4314/bcse.v35i1.11 -
Boron nitrogen confidence 0.95
“Same context as above”
Zhang 等 - 2015 - Stoichiometric controlling of boroncarbonitride th DOI: 10.1063/1.4918684 -
confidence 0.9
“Explicit assignment: '~1380 and 750 for h-BN phase'.”
Chowdhury 等 - 2004 - Novel electrodeposition route for the synthesis of DOI: 10.1016/j.matlet.2004.05.079 -
Boron nitrogen confidence 0.9
“B-N bending peak at ~750 cm-1.”
El Khezraji 等 - 2022 - Synthesis of Novel Non-Isocyanate PolyurethaneFun DOI: 10.3390/polym14193934 -
confidence 0.9
“absorption peak caused by pyran ring's C-O-C vibration at 750.2 cm-1”
Gao 等 - 2023 - Extraction, structural characterization, and antio DOI: 10.3389/fnut.2023.1149137 -
confidence 0.9
“Explicit assignment in text: 'peak at 750 cm-1 corresponds to the vibration of an aromatic ring substituted at the positions 1 and 2'”
Paglia 等 - 2022 - Effect of ceramic nano-particles on the properties DOI: 10.1002/pc.26811 -
C-O single bond confidence 0.9
“Text states 'main peaks at 750 K can be assigned to CO and CO2'.”
Plis 等 - 2016 - Furniture wood waste as a potential renewable ener DOI: 10.1007/s10973-016-5611-7 -
C n single bond confidence 0.9
“attributed to CN”
Pozzi 等 - 2021 - Aiding the cleaning of four 19th-century Tsimshian DOI: 10.1186/s40494-021-00513-4
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