What absorbs at 999 cm⁻¹ in an FTIR spectrum?
A band near 999 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 6 cited sources
Possible functional-group assignments
| Functional group | Supporting facts | Cited sources | Top confidence |
|---|---|---|---|
| Silicon-oxygen (Si-O) | 1 | 1 | 1.0 |
| Alkyl C-H | 1 | 1 | 1.0 |
| Ring structure | 1 | 1 | 1.0 |
| Carbon dioxide | 1 | 1 | 1.0 |
| C c single bond | 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
“4000 3500 3000 2500 2000 1500 1000 stronger hydrogen bonding could be concluded from the double (cm-1) Wave Number 2919cm-1 2887cm-1 999cm-1 992cm-1 peaks at to and to in nanocomposites samples when compared with pure starch (Ding, Ainswort”
Glycerol/starch/Na+-montmorillonite nanocomposites: A XRD, FTIR, DSC and 1H NMR study DOI: 10.1016/j.carbpol.2010.10.018 -
C c single bond confidence 1.0
“In particular, ATRFTIR analysis of Cotton paper showed absorption at the band of cm-1, cm-1 999 as well as the C-C ring breathing band at ~1105 and the C-O-C glycosidic”
Banou 等 - 2023 - Oil Media on Paper Investigating the Interaction DOI: 10.3390/polym15112567 -
Carbon dioxide confidence 1.0
“The band at with a 2337.72cm-1 shoulder at is credited by free carbon dioxide 999.13cm-1 [41].”
Malla 等 - 2020 - Extraction and Characterization of Novel Natural H DOI: 10.1155/2020/1690178 -
Ring structure confidence 1.0
“peaks at 999 and 865 were assigned to the skeletal ring (Figure 1).”
In Vitro Interaction of Doxorubicin-Loaded Silk Sericin Nanocarriers with MCF-7 Breast Cancer Cells Leads to DNA Damage DOI: 10.3390/polym13132047 -
Alkyl C-H confidence 1.0
“PCD 227 282 309 354 363 connected with C-H stretching vibration, indicates the a,b,c,d The temperature of 1, 5, 10 and 50 % mass loss from the TG existence of unsaturated compounds, whereas bands at 999 curve, respectively cm-1, and 917 ass”
The effect of chain extender structure on the properties of new thermoplastic poly(carbonate–urethane)s derived from MDI DOI: 10.1007/s10973-016-5756-4 -
Silicon-oxygen (Si-O) confidence 1.0
“LLM confirmed rule peak-group candidate”
Tambara Junior 等 - 2021 - Effect of Alkaline Salts on Calcium Sulfoaluminate DOI: 10.3390/molecules26071938
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