Qhov sib txawv tseem ceeb ntawm kev zoo siab thiab kev nqus yog qhov excitation yog cov txheej txheem ntawm absorbing photon thiab txav mus rau qib siab zog whereas absorption yog cov txheej txheem ntawm kev hloov lub zog ntawm photon mus rau ib yam khoom.
Cov ntsiab lus nqus thiab ua kom muaj txiaj ntsig zoo hauv thaj chaw ntawm quantum mechanics, analytical chemistry, relativity, thiab ntau lwm yam. Koj xav tau kev nkag siab zoo ntawm cov ntsiab lus no kom nkag siab cov ntsiab lus ntawm cov teb no kom raug. Cov ntsiab lus ntawm kev nqus thiab kev zoo siab kuj yog lub hauv paus ntsiab lus hauv thaj tsam ntawm spectroscopy thiab spectrometry.
Kev zoo siab yog dab tsi?
Kev ua siab ntev yog kev hloov pauv ntawm lub cev uas nyob rau ntawm lub zog qis rau lub xeev muaj zog. Yog li, lo lus no tuaj yeem tham txog ib qho hluav taws xob khi rau lub nucleus ntawm lub xeev hauv av. Quantum mechanics qhia tias ib qho hluav taws xob tsuas tuaj yeem siv lub zog tshwj xeeb. Tsis tas li ntawd, qhov tshwm sim ntawm kev nrhiav ib qho hluav taws xob nyob nruab nrab ntawm cov xeev nyob ruaj khov no yog xoom. Yog li ntawd, lub zog sib txawv ntawm ob theem yog qhov tsis sib xws. Qhov ntawd txhais tau tias; ib qho hluav taws xob tuaj yeem nqus los yog tawm lub zog sib xws rau txhua qhov sib txawv ntawm lub xeev nyob ruaj ruaj, tab sis tsis nyob nruab nrab.
Daim duab 01: Kev zoo siab los ntawm Irradiation
Kev ua siab ntev yog cov txheej txheem ntawm kev nqus cov photon mus rau qib siab dua. Cov txheej txheem rov qab ntawm excitation yog emitting ib photon los mus rau qis zog. Yog hais tias lub zog ntawm qhov teeb meem photon loj txaus, lub electron yuav txav mus rau lub zog loj heev, yog li tshem tawm nws tus kheej ntawm lub atom. Peb hu nws "ionization".
Kev nqus yog dab tsi?
Absorption yog ib lo lus uas peb feem ntau siv los txheeb xyuas qee qhov ntau dhau los ua ib feem ntawm lwm qhov ntau. Nyob rau hauv chemistry, peb tsuas yog siv lub sij hawm nqus nyob rau hauv lub siab ntawm electromagnetic tsis. Kev nqus ntawm electromagnetic tsis yog hais txog cov txheej txheem hloov pauv ntawm lub zog ntawm photon mus rau qhov system uas photon tau absorbed. Nyob rau hauv tus txheej txheem ntawm kev nqus, qhov teeb meem photon ploj.
Cia peb coj ib lub cev nrog ib lub tshuab hluav taws xob khi rau lub nucleus. Piv txwv li, xav tias lub electron nyob hauv av. Yog tias photon sib tsoo nrog cov electron, lub electron tuaj yeem nqus cov photon nyob ntawm lub zog ntawm photon. Ntxiv mus, yog tias lub zog ntawm photon sib npaug ntawm lub zog sib txawv ntawm lub xeev hauv av thiab lwm lub xeev, cov electron tuaj yeem nqus cov photon. Txawm li cas los xij, yog tias lub zog ntawm photon tsis sib npaug ntawm lub zog sib txawv, lub photon yuav tsis nqus. Lub photon muaj lub zog pib vim qhov loj ntawm photon. Nws ua rau lub zog hloov ntawm electron thaum lub photon absorbed. Absorption yog lub hauv paus ntsiab lus tseem ceeb ntawm kev nqus thiab emission spectra.
Daim duab 02: Absorption Spectra rau Carotenoids
Qhov txawv ntawm Kev Txaus Siab thiab Kev nqus yog dab tsi?
Excitation yog qhov hloov pauv ntawm lub xeev ntawm lub cev mus rau lub xeev ntawm lub zog siab dua thaum nqus tau yog lub zog hloov ntawm photon mus rau ib qho system. Yog li ntawd, qhov sib txawv tseem ceeb ntawm excitation thiab absorption yog qhov excitation yog cov txheej txheem ntawm absorbing ib photon thiab txav mus rau lub zog siab dua whereas absorption yog cov txheej txheem ntawm hloov lub zog ntawm ib tug photon mus rau ib yam khoom.
Ntxiv mus, kom muaj kev zoo siab tshwm sim, kev nqus yuav tsum tshwm sim, thiab kom nqus tau tshwm sim, lub kaw lus yuav tsum zoo siab. Yog li ntawd, kev nqus thiab excitation yog kev sib koom ua ke.
Summary – Excitation vs Absorption
Kev ua siab ntev thiab nqus tau zoo sib xws. Qhov sib txawv tseem ceeb ntawm excitation thiab absorption yog tias excitation yog cov txheej txheem ntawm absorbing ib photon thiab txav mus rau lub zog siab dua whereas absorption yog cov txheej txheem ntawm hloov lub zog ntawm photon mus rau ib yam khoom.
