What absorbs at 646 cm⁻¹ in an FTIR spectrum?
A band near 646 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
Ātra atbilde
A band near 646 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.
Iespējamie funkcionālo grupu piešķīrumi
| Funkcionālā grupa | Atbalstošie fakti | Citētie avoti | Augstākā pārliecība |
|---|---|---|---|
| Metal oxygen | 3 | 3 | 1,0 |
| Borate | 1 | 1 | 1,0 |
| Chlorine | 1 | 1 | 1,0 |
| Hydroxyl (O-H) | 1 | 1 | 1,0 |
| Methoxy (OCH3) | 1 | 1 | 1,0 |
| Methacrylate | 1 | 1 | 1,0 |
| C-O single bond | 1 | 1 | 1,0 |
| Acetate | 1 | 1 | 1,0 |
| N-O bond | 1 | 1 | 1,0 |
| Ring structure | 1 | 1 | 1,0 |
| C#c | 1 | 1 | 0,6 |
Rangs atspoguļo uzkrātos literatūras pierādījumus, nevis vienu autoritatīvu noteikumu. Vienmēr apstipriniet atbilstoši parauga kontekstam.
Iespējamie materiāli
| Materiāls | Atbalstošie pīķi | Pārklājošās grupas | Citētie avoti |
|---|---|---|---|
| quercetin | 646, 1745, 1612 | Hydroxyl (O-H) | 1 |
Materiāli tiek parādīti tikai tad, ja šo joslu un vismaz vienu papildu raksturīgo pīķi atbalsta tā pati literatūras kopa.
Spektra loģika
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 646 cm⁻¹ is usually not enough for material identification by itself.
Reālās pasaules izmantošana
Šāda veida vaicājums ir izplatīts polimēru identificēšanā, nezināmas plastmasas skrīningā, kvalitātes kontroles problēmu risināšanā, pārstrādāto materiālu pārbaudē un ar literatūru pamatotā pīķu piešķīruma pārskatā.
Biežākās kļūdas
- Vienas izolētas joslas uzskatīšana par materiāla pierādījumu, nepārbaudot vismaz vienu vai divus atbalsta pīķus.
- Ignorējot pārklāšanos: vairākas funkcionālās grupas var dot ieguldījumu tuvu tam pašam viļņa skaitlim.
- Izlaist validāciju, ja piedevas, maisījumi, oksidācija vai piesārņojums var izkropļot spektru.
Verifikācijas padoms
Ja joprojām pastāv neskaidrība, apstipriniet hipotēzi ar DSC, GC-MS vai TGA, īpaši maisījumiem, noārdītiem paraugiem un pildītiem polimēriem.
Literatūra aiz šiem piešķīrumiem
-
Ring structure pārliecība 1,0
“IR and Raman bands observed at 646, 1115, 1587 and 646, cm-1 1110, 1270 is due to the ring bending or stretching and stretching vibrations of C-NO and C-O”
Dalal 等 - 2015 - Structural, electrical, ferroelectric and mechanic DOI: 10.1039/C5RA10501C. -
Hydroxyl (O-H) pārliecība 1,0
“Acorrdcm-1 that were assigned to O-H located at 3369 and 655 literatures,12(cid:4)16 cm-1 the peak of 646 was attributed ing to”
Zhang 等 - 2019 - Synthesis of TiB2 Powders with Hexagonal Morpholog DOI: 10.1166/jnn.2019.16750 -
pārliecība 1,0
“cm-1 cm-1 parameter in this study, we attempted to estimate those 768 (C-Cl stretch = alkyl halides) and 646 (- C:C-H: phytochemicals quantitatively in MEAIL.”
Identification of food preservative, stress relief compounds by GC–MS and HR-LC/Q-TOF/MS; evaluation of antioxidant activity of Acalypha indica leaves methanolic extract (in vitro) and polyphenolic fraction (in vivo) DOI: 10.1007/s13197-017-2590-z) -
pārliecība 1,0
“The presence of other bands at 646 and 532 are attributed to stretching vibration ν (Zn-O), this confirm the formation of metal complex [35].”
Refat 等 - 2021 - QuercetinZinc complex and stem cells A new drug DOI: 10.1371/journal.pone.0246265 -
Borate pārliecība 1,0
“grinding and mixing processes that may affect the borate peak intensity slightly, for example the cm-1 sharp peak at 646 for the physical mixture sample with 0.25 wt.% B 2O may indicate longer sharp peak at 646 cm-1 for the physical mixture”
Development of FTIR Spectroscopy Methodology for Characterization of Boron Species in FCC Catalysts DOI: 10.3390/catal10111327 -
Metal oxygen pārliecība 0,95
“Text: 'coordinated Al-O was indicated by bands at 747, 646, and 486'”
Retnoningtyas 等 - 2022 - Synthesis and Characterization of Methionine-Funct DOI: 10.33263/BRIAC125.58455859
Vai jums ir spektrs ar šo joslu?
Augšupielādējiet savu FTIR spektru un dažu sekunžu laikā iegūstiet pilnu interpretācijas ziņojumu — maksimumu piešķīrumus ar literatūras atsaucēm, bibliotēku saskaņošanu un pārliecības līmeņa pierādījumu ķēdi.