Video: Dab tsi ntawm NMR ntsuas feem ntau ntawm koj NMR spectra tau txais?
2024 Tus sau: Miles Stephen | [email protected]. Kawg hloov kho: 2023-12-15 23:36
Feem ntau feem ntau hom NMR yog proton thiab carbon-13 NMR spectroscopy , tab sis nws yog siv tau rau ib qho twg zoo ntawm cov qauv uas muaj nuclei muaj spin. NMR spectra yog tshwj xeeb, daws teeb meem zoo, analytically tractable thiab feem ntau xav tau heev rau cov me me molecules.
Kuj nug, NMR spectrum qhia dab tsi?
Nuclear Sib Nqus Resonance ( NMR ) spectroscopy yog cov txheej txheem analytical chemistry siv hauv kev tswj kom zoo thiab reserach rau kev txiav txim siab cov ntsiab lus thiab purity ntawm tus qauv nrog rau nws cov qauv molecular. Piv txwv li, NMR tuaj yeem txheeb xyuas cov khoom sib xyaw uas muaj cov khoom sib xyaw ua ke.
Ib yam li ntawd, vim li cas TMS siv raws li tus qauv hauv NMR? Siv hauv NMR spectroscopy Vim nws cov volatility siab, TMS tuaj yeem yooj yim evaporated, uas yooj yim rau kev rov qab los ntawm cov qauv tshuaj ntsuam xyuas los ntawm NMR spectroscopy. Vim hais tias tag nrho kaum ob hydrogen atoms nyob rau hauv ib tug tetramethylsilane molecule yog sib npaug, nws 1H NMR spectrum muaj ib tug singlet.
Ib yam li ntawd, nws tau nug, hom nuclei qhia NMR spectra dab tsi?
NMR tshwm sim vim absorbance ntawm xov tooj cua zaus hluav taws xob ua rau "flipping" ntawm nuclear spin los ntawm qis mus rau siab zog spin xeev. Thaum tsis yog tag nrho nuclei yog NMR active (eg. 12C thiab 16O yog inactive), qhov tseem ceeb tshaj plaws nuclei rau organic chemists yog 1H thiab 13C (ob leeg nrog nuclear spin = 1/2).
Lub spectrum tau txais hauv NMR spectroscopy li cas?
Ib nmr kev yog kis tau los ntawm kev sib txawv lossis cheb qhov chaw sib nqus ntawm ib qho me me thaum saib cov teeb liab rf los ntawm cov qauv. Ib qho txheej txheem zoo sib npaug yog sib txawv ntawm qhov zaus ntawm rf hluav taws xob thaum tuav lub teb sab nraud tas li.
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