C=n — FTIR-absorptions-toppe og tildelinger

Hurtigt svar

C=n tildeles normalt ved at lede efter en tilbagevendende klynge af karakteristiske toppe frem for et præcist lærebogsnummer. Tabellen nedenfor viser, hvor litteraturen oftest placerer denne gruppe i FTIR, rangeret efter akkumuleret evidens.

Karakteristiske FTIR-toppe for C=n

Viser de 30 bedst understøttede toppe ud af 227 i alt for C=n.

Spektrumlogik

En funktionel gruppetildeling bliver mere sikker, når flere forventede bånd optræder sammen. Brug denne side til at finde de bedst understøttede peaks, og bekræft derefter, at den samme prøve udviser et sammenhængende mønster snarere end et enkelt isoleret hit.

Anvendelse i virkeligheden

Disse sider er nyttige til analyse af ukendte materialer, topforklaring i rapporter, polymerfejlfinding og verifikation af, om en kandidatmaterialefamilie er kemisk plausibel.

Almindelige fejl

• Brug af én funktionel-gruppe-side som en komplet materialebedømmelse uden at kontrollere resten af spektret.
• Antager, at det stærkeste bånd altid er det mest diagnostiske.
• At glemme, at forarbejdning, tilsætningsstoffer, ældning og blandinger kan flytte eller udvide forventede toppe.

Verifikationsrådgivning

Brug DSC, GC-MS eller TGA, når flere materialefamilier deler lignende bånd, eller når blandings-effekter gør FTIR-tildelingen usikker.

Litteratur bag disse tildelinger

• 1489 cm⁻¹ tillid 1,0

  “cm-1 absorbance of the IR band at 3604 The decrease of the absorbance of the IR band at 1489 indicates a -C=N-benzene smaller weight of the ring vibrational mode after the interaction of the GO sheets with PDITC, this being in good agreemen”

  Baibarac 等 - 2019 - Adsorption of 1,4-phenylene diisothiocyanate onto DOI: 10.1038/s41598-019-48314-x
• 1519 cm⁻¹ tillid 1,0

  “The bands centered at 1519 and 1454 are assigned to C=N stretching of quinoid and C-N stretching of benzenoid rings, respectively;”

  Synthesis of novel conducting polyaniline composites based on seaweed Enteromorpha compressa macro-alga powder DOI: 10.1007/s00289-020-03191-7
• 1627 cm⁻¹ tillid 1,0

  “cm-1, For quantification, absorbance of C=O stretch cantered at 1754 between wave number of 1750 - cm-1 cm-1, 1730 was selected for Aspirin and absorbance of C=N stretch cantered at 1627 between 1690 cm-1 - 1620 was used for Omeprazole.”

  Chandarana 和 Kapupara - 2020 - Fourier Transform Infrared Spectrophotometry An E DOI: 10.30744/brjac.2179-3425.AR-25-2020
• 1605 cm⁻¹ tillid 1,0

  “LLM confirmed rule peak-group candidate”

  Synthesis, crystal structures, quantum chemical studies and corrosion inhibition potentials of 4-(((4-ethylphenyl)imino)methyl)phenol and (E)-4-((naphthalen-2-ylimino) methyl) phenol Schiff bases DOI: 10.1016/j.molstruc.2017.06.104
• 1497 cm⁻¹ tillid 1,0

  “The peaks observed at 1497, 1466 and cm-1 205 1400 are attributed to C=N stretching in aromatic compounds.”

  Effect of polyaniline (PANI) on Poly(vinylidene fluoride-co-hexaflouro propylene) (PVDF-co-HFP) polymer electrolyte membrane prepared by breath figure method DOI: 10.1016/j.polymertesting.2017.03.012
• 2270 cm⁻¹ tillid 1,0

  “Obviously, the characteristic is interesting that the viscosity of the HTPE/HDIB system cm-1 peak height at 2270 corresponding to-N=C=O”

  Curing reaction kinetics of HTPE polymer studied by simultaneous rheometry and FTIR measurements DOI: 10.1007/s10973-016-5485-8
• 1800 cm⁻¹ tillid 1,0

  “cm-1 The IR absorption bands in the region between 1800 and 1500 were mainly assigned to the C=C, C=N, and C=O stretching vibrations (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
• 1602 cm⁻¹ tillid 1,0

  “cm-1 cm-1 1086 C-N stretching in amines, 1530 C=C Authors' contributions cm-1 stretching, 1602 C=N stretching (in ring),”

  Hanif 和 Zaman - 2017 - Thiolation of arabinoxylan and its application in DOI: 10.1186/s40199-017-0172-2