What absorbs at 781 cm⁻¹ in an FTIR spectrum?
A band near 781 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
Kiire vastus
A band near 781 cm⁻¹ is usually interpreted by checking which functional groups repeatedly co-occur there in the literature, then confirming at least one or two additional peaks in the same sample. This page ranks those assignments by accumulated evidence rather than by a single fixed textbook rule.
Võimalikud funktsionaalrühmade määramised
| Funktsionaalrühm | Toetavad faktid | Tsiteeritud allikad | Kõrgeim usaldusväärsus |
|---|---|---|---|
| Siloxane (Si-O-Si) | 2 | 2 | 1,0 |
| Silicon-oxygen (Si-O) | 2 | 2 | 1,0 |
| Silicon (Si) | 2 | 2 | 1,0 |
| Aromatic ring | 2 | 2 | 1,0 |
| Nucleic acid | 1 | 1 | 1,0 |
| Ring structure | 1 | 1 | 1,0 |
| C c single bond | 1 | 1 | 1,0 |
| Oxalate | 1 | 1 | 1,0 |
| Alkyl C-H | 1 | 1 | 1,0 |
| Secondary amine | 1 | 1 | 1,0 |
| C n single bond | 1 | 1 | 1,0 |
| Amide | 1 | 1 | 1,0 |
| Chlorine | 1 | 1 | 1,0 |
Reiting kajastab kogunenud kirjanduslikke tõendeid, mitte ühte autoriteetset reeglit. Kinnitage alati oma proovi kontekstis.
Spektri loogika
This band becomes meaningful only when read with its neighboring peaks. In practice, analysts first look at the assignments above, then check whether the same sample also shows other peaks expected for the same structural motif. A lone band near 781 cm⁻¹ is usually not enough for material identification by itself.
Reaalse maailma kasutus
Seda tüüpi päring on tavaline polümeeri tuvastamisel, tundmatu plasti sõeluuringul, kvaliteedikontrolli probleemide lahendamisel, ringlussevõetud materjali kontrollimisel ja kirjandusel põhineval piirkinnituste ülevaatel.
Levinud vead
- Ühe isoleeritud riba käsitlemine materjali tõendina ilma vähemalt ühte või kahte toetavat piiki kontrollimata.
- Ülekattumise ignoreerimine: mitu funktsionaalrühma võivad anda panuse sama lainearvu lähedal.
- Valideerimise vahelejätmine, kui lisandid, segud, oksüdatsioon või saastumine võivad spektrit moonutada.
Kontrollimise nõuanne
Kui ebakindlus püsib, kinnitage hüpotees DSC, GC-MS või TGA abil, eriti segude, lagunenud proovide ja täidetud polümeeride puhul.
Nende määramiste taga olev kirjandus
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Silicon (Si) usaldusväärsus 1,0
“The cm-1 cm-1 absorption band at 781 and 1050 are assigned to the v 1symmetric vibration and v 3asymmetrical stretching vibration of the Si-O bond.”
Ilmi 等 - 2020 - Multi-analytical characterizations of prehistoric DOI: 10.1016/j.microc.2020.104738 -
usaldusväärsus 1,0
“cm-1, The spectra produced strong peaks at 521.38 and 516.39 corresponding to the C-I (stretching) functional group of alkyl halides, for the leaf and stem, respectively, as well as cm-1 a strong peak corresponding to the C-Cl (stretching)”
Phytochemical Composition of Combretum molle (R. Br. ex G. Don.) Engl. & Diels Leaf and Stem Extracts DOI: 10.3390/plants12081702 -
Alkyl C-H usaldusväärsus 1,0
“Both samples treated with TEMPO derivatives show the characteristic signals of their functional groups: in particular, the band at 1709 and 1717 cm-1 can be associated with the cm-1 functional groups: in particular, the band at 1709 and 171”
Cicogna 等 - 2022 - Surface Functionalization of Face Masks with Cold DOI: 10.3390/molecules27238632 -
Oxalate usaldusväärsus 1,0
“The FTIR spectrum peaks at 780.7, 1336.4, and 1631.0 all correspond to reported peak positions for sodium oxalate [16].”
Evaluation of Formate Salt PCM’s for Latent Heat Thermal Energy Storage DOI: 10.3390/en14030765 -
usaldusväärsus 1,0
“The vibrational band centred at 781 cm-1 is ascribed to the stretching mode modes due to the formation of nonbridge oxygen.”
Effect of Yb3+ on the Structural and Visible to Near-Infrared Wavelength Photoluminescence Properties in Sm3+-Yb3+-Codoped Barium Fluorotellurite Glasses DOI: 10.3390/ma15093314 -
C c single bond usaldusväärsus 1,0
“Furthermore, for the spectrum of cm-1 1545, and 1552 cm-1, respectively, can be attributed to the C-C stretching vibration of benzene ring HACSa, HACCa, HACPc, and HACGa, absorption peaks at 781, 767, 772, 735, 739 corresponded 1478cm-1 [3,”
Modification of Hydroxypropyltrimethyl Ammonium Chitosan with Organic Acid: Synthesis, Characterization, and Antioxidant Activity DOI: 10.3390/polym12112460 -
Silicon (Si) usaldusväärsus 1,0
“The peaks at 113 cm-1 cm-1 876 cm-1 and 781 cm-1 were assigned to Si-O-Si symmetric stretching vibrations [36].”
Adsorption of Hexavalent Chromium Using Banana Pseudostem Biochar and Its Mechanism DOI: 10.3390/su10114250 -
Nucleic acid usaldusväärsus 1,0
“LLM confirmed rule peak-group candidate”
Zelig 等 - 2010 - Biochemical analysis and quantification of hematop DOI: 10.1117/1.3442728(cid:4)
Kas teil on selle ribaga spekter?
Laadige üles oma FTIR spekter ja saage sekunditega täielik tõlgendusaruanne — piikide määramised kirjandusviidetega, raamatukogu vasted ja usaldusväärsusega hinnatud tõendite ahel.