Hvad absorberer ved 1500 cm⁻¹ i et FTIR-spektrum?
Et bånd nær 1500 cm⁻¹ kan pege på flere funktionelle grupper. Nedenfor er de mest sandsynlige tildelinger, rangeret efter hvor meget publiceret bevis der understøtter hver — hver enkelt spores til litteratur (DOI) og krydsvalideres mod vores 130.000+ referencespektre og vidensgraf.
Backed by 8 cited sources
Hurtigt svar
Et bånd nær 1500 cm⁻¹ fortolkes normalt ved at kontrollere, hvilke funktionelle grupper der gentagne gange forekommer der i litteraturen, og derefter bekræfte mindst en eller to yderligere peaks i den samme prøve. Denne side rangerer disse tildelinger efter akkumuleret evidens snarere end efter en enkelt fast lærebogsregel.
Mulige funktionelle gruppetildelinger
| Funktionel gruppe | Understøttende fakta | Citerede kilder | Højeste tillid |
|---|---|---|---|
| Amide | 45 | 38 | 1,0 |
| Aromatic ring | 37 | 33 | 1,0 |
| Carboxyl (COOH) | 26 | 22 | 1,0 |
| Acetate | 25 | 23 | 1,0 |
| Methacrylate | 24 | 22 | 1,0 |
| Alkyl C-H | 23 | 21 | 1,0 |
| Alkene (C=C) | 20 | 19 | 1,0 |
| Carbonyl (C=O) | 16 | 14 | 1,0 |
| N h | 15 | 14 | 1,0 |
| Ketone | 14 | 12 | 1,0 |
| Ester | 14 | 12 | 1,0 |
| C-O single bond | 12 | 12 | 1,0 |
| Hydroxyl (O-H) | 12 | 10 | 1,0 |
| Ring structure | 11 | 10 | 1,0 |
| Methoxy (OCH3) | 10 | 10 | 1,0 |
| C c single bond | 8 | 8 | 1,0 |
| N-O bond | 8 | 7 | 1,0 |
| Carbohydrate | 8 | 5 | 1,0 |
| Lignin | 7 | 6 | 1,0 |
| Water (H2O) | 7 | 5 | 1,0 |
| Carbonate | 6 | 5 | 1,0 |
| Secondary amine | 4 | 4 | 1,0 |
| Protein | 3 | 3 | 1,0 |
| Nucleic acid | 2 | 2 | 1,0 |
| Silicon-oxygen (Si-O) | 2 | 2 | 1,0 |
| Borate | 2 | 2 | 1,0 |
| Hydrogen bond | 2 | 2 | 1,0 |
| Lipid | 1 | 1 | 1,0 |
| Amino acid | 1 | 1 | 1,0 |
| Metal oxygen | 1 | 1 | 1,0 |
| N n bond | 1 | 1 | 1,0 |
| C=n | 1 | 1 | 1,0 |
| Siloxane (Si-O-Si) | 1 | 1 | 1,0 |
| Silicate | 1 | 1 | 1,0 |
| Chlorine | 1 | 1 | 1,0 |
| Fatty acid | 1 | 1 | 1,0 |
| C n single bond | 1 | 1 | 1,0 |
| Nitrogen heterocycle | 1 | 1 | 1,0 |
| Protein random coil | 1 | 1 | 1,0 |
| Thiocarbonyl | 1 | 1 | 1,0 |
| Ammonium | 1 | 1 | 1,0 |
| Silicon (Si) | 1 | 1 | 1,0 |
| Methyl | 1 | 1 | 0,9 |
| Silanol (Si-OH) | 1 | 1 | 0,9 |
| Phospholipid | 1 | 1 | 0,7 |
| Phosphate (PO4) | 1 | 1 | 0,7 |
| N eq o | 1 | 1 | 0,7 |
| Nitro (NO2) | 1 | 1 | 0,6 |
Rangering afspejler akkumuleret litteraturevidence, ikke en enkelt fast regel. Bekræft altid mod din prøvekontekst.
Mulige materialer
| Materiale | Understøttende toppe | Overlappende grupper | Citerede kilder |
|---|---|---|---|
| Methacrylate | 1500, 873, 1725 | Acetate | 1 |
| CO | 1500, 1670, 1620 | Acetate | 1 |
| cellulose | 1500, 1735, 1650 | Acetate, Amide | 1 |
Materialer vises kun, når den samme litteraturpulje understøtter dette bånd og mindst en yderligere karakteristisk top.
Spektrumlogik
Dette bånd bliver meningsfuldt kun, når det læses sammen med sine nabotoppe. I praksis ser analytikere først på tildelingerne ovenfor, og kontrollerer derefter, om den samme prøve også viser andre toppe, der forventes for det samme strukturelle motiv. Et enkelt bånd nær 1500 cm⁻¹ er normalt ikke nok til materialeidentifikation alene.
Anvendelse i virkeligheden
Denne type forespørgsel er almindelig ved polymeridentifikation, screening af ukendt plast, fejlfinding i kvalitetskontrol, verifikation af genanvendt materiale og litteraturunderstøttet gennemgang af peak-tildeling.
Almindelige fejl
- Behandling af et isoleret bånd som bevis på et materiale uden at kontrollere mindst en eller to understøttende toppe.
- Ignorerer overlap: flere funktionelle grupper kan bidrage nær samme bølgetal.
- Spring validering over, når additiver, blandinger, oxidation eller forurening kan forvrænge spektret.
Verifikationsrådgivning
Når tvetydighed fortsat består, valider hypotesen med DSC, GC-MS eller TGA, især for blandinger, nedbrudte prøver og fyldte polymerer.
Litteratur bag disse tildelinger
-
tillid 1,0
“The spectra in the core region cm-1, also show a band at 1500 which can be attrib3.1 Calcium oxalate monohydrate (COM) (N-H uted to amide II bond stretching) and is not”
High precision mapping of kidney stones using mu;IR spectroscopy to determine urinary lithogenesis DOI: 10.1002/jbio.201300201 -
Lignin tillid 1,0
“Significantly, an increase in hemicellulose cm-1 and cellulose peaks around 1700 was determined, while the lignin peak around cm-1 1500 disappeared completely.”
Can 等 - 2023 - Choline Chloride-Based Deep Eutectic Solvent-Treat DOI: 10.3390/f14030569 -
Alkene (C=C) tillid 1,0
“cm-1 (C=C stretch in phenyl rings) and the reduction in the intensity of the The disappearance of the band at 1500 cm-1”
Chhokkar 等 - 2020 - Electrical and Structural Characterization of 100 DOI: 10.1063/5.0023335 -
Water (H2O) tillid 1,0
“Additionally, the presence of noise in the 1000-1100 and 1500cm-1 1800 regions due to high glass filler content and background water vapour absorbance, respectively, could be detected in some samples.”
Methacrylate peak determination and selection recommendations using ATR-FTIR to investigate polymerisation of dental methacrylate mixtures DOI: 10.1371/journal.pone.0252999 -
Aromatic ring tillid 1,0
“cm-1, Aromatic rings exhibit, most of the times, a characteristic band at approximately 1500 corresponding to benzene ring stretching vibrations.”
Esteves 等 - 2013 - CHEMICAL CHANGES OF HEAT TREATED PINE AND EUCALYPT DOI: 10.4067/S0718-221X2013005000020 -
Aromatic ring tillid 1,0
“Absorptions around 1500 arise ylacetamide, lithium chloride under homogeneous conditions 1335-1316cm(cid:3)1 from the aromatic ring vibrations.”
Functional biocompatible magnetite⠍cellulose nanocomposite fibrous networks: Characterization by fourier transformed infrared spectroscopy, X-ray powder diffraction and field emission scanning electron microscopy analysis DOI: 10.1016/j.saa.2014.10.035 -
Carboxyl (COOH) tillid 1,0
“The band intena band that could be ascribed to COOH throughout the potential 1300cm-1 1500cm-1 sities for CO(B) are multiplied by a factor 3.3, as in Figs.”
Hanawa 等 - 2009 - In situ ATR-FTIR study of bulk CO oxidation on a p DOI: 10.1016/j.electacta.2009.05.061 -
Carbohydrate tillid 1,0
“Additionally, the FTIR marker bands in the 1500cm-1 1250 region may be due to the effects of the backbone conformation, sugar puckering modes, and glycosidic bond rotation (Banyay et al., 2003).”
A novel FTIR discrimination based on genomic DNA for species-specific analysis of meat and bone meal DOI: 10.1016/j.foodchem.2019.05.088
Har du et spektrum med dette bånd?
Upload dit FTIR-spektrum og få en fuld fortolkningsrapport — peak-tildelinger med litteraturhenvisninger, biblioteksmatch og en litteraturunderstøttet analyse — på få sekunder.