Qhov sib txawv tseem ceeb ntawm IR thiab UV thiab pom spectroscopy yog tias IR spectroscopy siv lub zog qis qis ntawm cov spectrum, thaum UV thiab pom spectroscopy siv UV thiab pom thaj tsam ntawm electromagnetic spectrum.
Muaj ntau cov txheej txheem spectroscopic raws li qhov wavelength ntau yam uas tau ntsuas. IR thiab UV thiab pom spectroscopy yog ob txoj kev spectroscopic.
IR Spectroscopy yog dab tsi?
IR spectroscopy lossis infrared spectroscopy (tseem hu ua vibrational spectroscopy) yog qhov ntsuas ntawm kev cuam tshuam ntawm IR hluav taws xob nrog qhov teeb meem los ntawm kev nqus, emission, lossis kev xav. Txoj kev no muaj txiaj ntsig zoo hauv kev kawm thiab txheeb xyuas cov tshuaj lom neeg lossis cov pab pawg ua haujlwm hauv cov khoom, kua, lossis cov ntawv gaseous. Ntxiv mus, peb tuaj yeem siv IR spectroscopy los qhia cov ntaub ntawv tshiab thiab txheeb xyuas thiab txheeb xyuas cov qauv paub thiab tsis paub.
IR spectroscopy suav nrog cov zaus nqus los ntawm cov molecules uas yog tus yam ntxwv ntawm cov qauv. Feem ntau, cov kev nqus no tshwm sim ntawm cov zaus resonant (nws yog qhov zaus ntawm cov hluav taws xob nqus hluav taws xob uas sib tw nrog lub vibrational zaus). Tshwj xeeb tshaj yog, nyob rau hauv Born-Oppenheimer thiab harmonic approximations, resonant zaus yog txuam nrog rau cov hom kev co uas sib xws rau lub molecular hluav taws xob hauv av lub xeev muaj peev xwm lub zog nto. Ntxiv mus, resonant zaus muaj feem xyuam rau lub zog ntawm daim ntawv cog lus thiab qhov loj ntawm cov atoms ntawm txhua qhov kawg. Yog li ntawd, qhov zaus ntawm cov kev vibrations yog txuam nrog ib qho tshwj xeeb ntawm cov lus tsa suab thiab ib hom kev sib cog lus.
UV thiab Pom pom Spectroscopy yog dab tsi?
UV thiab pom spectroscopy lossis UV-vis spectroscopy yog cov cuab yeej tshuaj ntsuam xyuas uas ntsuas cov qauv ua kua los ntawm kev ntsuas nws lub peev xwm nqus hluav taws xob hauv cheeb tsam ultraviolet thiab pom spectral. Qhov no txhais tau hais tias cov txheej txheem nqus spectroscopic no siv lub teeb tsis pom hauv cov cheeb tsam pom thiab nyob ib sab hauv electromagnetic spectrum. Absorption spectroscopy deals with the excitation of electrons (kev txav ntawm ib qho hluav taws xob los ntawm lub xeev hauv av mus rau lub xeev zoo siab) thaum cov atoms hauv cov qauv nqus lub zog.
Cov khoom siv hluav taws xob ua rau muaj qhov tshwm sim hauv cov molecules uas muaj pi electrons lossis tsis yog cov khoom siv hluav taws xob. Yog hais tias cov electrons ntawm cov molecules nyob rau hauv cov qauv tuaj yeem ua tau yooj yim zoo siab, tus qauv tuaj yeem nqus tau ntev wavelengths. Yog li ntawd, cov electrons nyob rau hauv pi bonds los yog non-bonding orbitals tuaj yeem nqus tau lub zog los ntawm lub teeb nthwv dej hauv UV lossis pom ntau yam.
Qhov txiaj ntsig tseem ceeb ntawm UV-Visible spectrophotometer suav nrog kev ua haujlwm yooj yim, kev tsim tawm siab, kev txheeb xyuas tus nqi zoo, thiab lwm yam. Tsis tas li ntawd, nws tuaj yeem siv ntau yam wavelengths los ntsuas cov ntsuas ntsuas. Cov khoom tseem ceeb ntawm UV-pom spectroscopy muaj xws li lub teeb ci, tus qauv tuav, diffraction gratings nyob rau hauv lub monochromator, thiab ib tug detector.
A UV-pom spectrophotometer tuaj yeem siv los ntsuas cov kuab tshuaj hauv cov tshuaj. Cov cuab yeej no tuaj yeem siv los ntsuas cov ntsuas ntsuas xws li cov hlau hloov pauv thiab cov khoom sib txuas ntawm cov organic sib txuas (molecules uas muaj cov ntawv sib hloov pi). Peb tuaj yeem siv cov cuab yeej no los kawm txog cov kev daws teeb meem, tab sis qee zaum cov kws tshawb fawb siv cov txheej txheem no los tshuaj xyuas cov khib nyiab thiab cov pa phem.
Qhov txawv ntawm IR thiab UV thiab pom pom Spectroscopy yog dab tsi?
Spectroscopy yog kev kawm txog kev nqus thiab emission ntawm lub teeb thiab lwm yam hluav taws xob los ntawm teeb meem. Muaj ntau hom, xws li IR spectroscopy thiab UV-pom spectroscopy. Qhov sib txawv tseem ceeb ntawm IR thiab UV thiab pom spectroscopy yog tias IR spectroscopy siv lub zog qis qis ntawm cov spectrum, thaum UV thiab pom spectroscopy siv UV thiab pom thaj tsam ntawm electromagnetic spectrum.
Hauv qab no yog cov ntsiab lus ntawm qhov sib txawv ntawm IR thiab UV thiab pom spectroscopy hauv daim ntawv tabular.
Summary – IR thiab UV vs Pom pom Spectroscopy
Spectroscopy yog ib qho tseem ceeb analytical txheej txheem pab tau nyob rau hauv kev kawm cov tshuaj sib txawv. IR spectroscopy thiab UV-pom spectroscopy yog ob hom kev ntsuas no. Qhov sib txawv tseem ceeb ntawm IR thiab UV thiab pom spectroscopy yog tias IR spectroscopy siv lub zog qis qis ntawm cov spectrum, thaum UV thiab pom spectroscopy siv UV thiab pom thaj tsam ntawm electromagnetic spectrum.
