What absorbs at 774 cm⁻¹ in an FTIR spectrum?
A band near 774 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 774 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 |
|---|---|---|---|
| Silicon-oxygen (Si-O) | 2 | 2 | 1,0 |
| Hydroxyl (O-H) | 1 | 1 | 1,0 |
| C c single bond | 1 | 1 | 1,0 |
| N h | 1 | 1 | 1,0 |
| Amide | 1 | 1 | 1,0 |
| Water (H2O) | 1 | 1 | 1,0 |
| Alkyl C-H | 1 | 1 | 1,0 |
| Aromatic ring | 1 | 1 | 1,0 |
| Siloxane (Si-O-Si) | 1 | 1 | 0,9 |
Reiting kajastab kogunenud kirjanduslikke tõendeid, mitte ühte autoriteetset reeglit. Kinnitage alati oma proovi kontekstis.
Võimalikud materjalid
| Materjal | Toetavad piigid | Kattuvad rühmad | Tsiteeritud allikad |
|---|---|---|---|
| PVA | 774, 1660, 2930 | Hydroxyl (O-H) | 1 |
| ZnO | 774, 1400, 3430 | Hydroxyl (O-H) | 1 |
| CuO | 774, 453, 1000 | Hydroxyl (O-H) | 1 |
| glucose | 774, 1740, 1400 | Hydroxyl (O-H) | 1 |
| magnetite | 774, 1740, 1263 | Hydroxyl (O-H), Silicon-oxygen (Si-O) | 1 |
| quartz | 774, 800, 3053 | Silicon-oxygen (Si-O), Hydroxyl (O-H) | 1 |
Materjale kuvatakse ainult siis, kui sama kirjanduse kogum toetab seda riba ja vähemalt ühte täiendavat iseloomulikku piiki.
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 774 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
-
usaldusväärsus 1,0
“cm-1 (ii) The peak at 774 can be attributed to 10 Zn (Glass) 3.8 3.6 3.5 symmetric stretching vibrations of P - O - P 10 Zn (comp) 5.1 5.1”
Helmy 等 - 2021 - Preparation and Characterization of some Composite DOI: 10.21608/EJCHEM.2021.80482.3986 -
Aromatic ring usaldusväärsus 1,0
“The absorption peaks at 774 are assigned to aromatic C-H vibrations, indicating there are some aromatics with alkyl cm(cid:3)1 cm(cid:3)1 Transmittance substitution [21].”
Gradient separation of ⩾300°C distillate from low-temperature coal tar based on formaldehyde reactions DOI: 10.1016/j.fuel.2015.07.029 -
Water (H2O) usaldusväärsus 1,0
“The only exception is that the absorbing band belonging to 774 h in PA11-RH had a 39% increase in curve area, which might be due to the reversible reaction of water with amide”
Comparative Characterization of Hot-Pressed Polyamide 11 and 12: Mechanical, Thermal and Durability Properties DOI: 10.3390/polym13203553 -
usaldusväärsus 1,0
“cm-1 1710-1730 corresponds to the stretching vibrations of carbonyl groups (C=O), while the peaks corresponds to the stretching vibrations of carbonyl groups (C=O), while the peaks at 1534 and 774 cm-1 at 1534 and 774 correspond to the bend”
Synthesis of Linseed Oil-Based Waterborne Urethane Oil Wood Coatings DOI: 10.3390/polym10111235 -
Silicon-oxygen (Si-O) usaldusväärsus 1,0
“The studied quartz was detected with bands at 460.90 cm-1, 491.73 cm-1, 773.68 cm-1, and 1071.43 cm-1.”
Fawzy - 2021 - Separation of fine beryl from quartz via magnetic DOI: 10.37190/ppmp/132329 -
C c single bond usaldusväärsus 1,0
“829 C-C stretching 774 774 OH deformation 771”
Gallegos-Loya 等 - 2012 - An Optical Overview of Poly[mu(2)-L-alanine-mu(3)- DOI: 10.1100/2012/620189 -
usaldusväärsus 0,9
“Text: '774 cm-1 (P G1)' for glucose”
Landari 等 - 2018 - Pseudo-Continuous Flow FTIR System for Glucose, Fr DOI: 10.3390/mi9100517 -
Siloxane (Si-O-Si) usaldusväärsus 0,9
“explicit assignment in text”
Evaluation of polyvinyl alcohol–borax/agarose (PVA–B/AG) blend hydrogels for removal of deteriorated consolidants from ancient Egyptian wall paintings DOI: 10.1186/s40494-019-0264-z
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.