Kunamagama athile adala ukudideka olimini oluvamile lwansuku zonke. Phakathi kwala magama sinawo i-luminescence, i-fluorescence ne-phosphorescence. Ingabe ayalingana amagama? Ihluke kanjani futhi ngayinye ibhekisela kuphi?
Konke lokhu sizokubona kulesi sihloko, ngakho ungaphuthelwa.
Yini i-luminescence
Igama elithi luminescence ngokuyisisekelo libhekisela ekukhishweni kokukhanya. Endaweni yethu, izinto eziningi zikhipha ukukhanya ngenxa yamandla eziwathola elangeni, okuyinto Yibhizinisi elikhanya kakhulu elibonakala kithi. Ngokungafani nenyanga, ebonakala ikhipha ukukhanya, empeleni iveza ukukhanya kwelanga, isebenza ngendlela efanayo nesibuko samatshe esikhulukazi.
Ngokuyisisekelo, kunezinhlobo ezintathu eziyinhloko ze-luminescence: i-fluorescence, i-phosphorescence ne-chemiluminescence. Phakathi kwazo, i-fluorescence ne-phosphorescence zihlukaniswa njengezinhlobo ze-photoluminescence. Umehluko phakathi kwe-photoluminescence kanye ne-chemiluminescence usesimeni sokusebenza kwe-luminescence; Ku-photoluminescence, ukukhanya kusebenza njenge-trigger, kuyilapho ku-chemiluminescence, ukusabela kwamakhemikhali kuqala ukukhishwa kokukhanya.
Kokubili i-fluorescence ne-phosphorescence, okuyizinhlobo ze-photoluminescence, zincike ekhonweni lento lokumunca ukukhanya bese ngokulandelayo likukhiphe ngobude begagasi elide, okubonisa ukuncipha kwamandla. Nokho, Ubude besikhathi sale nqubo buhluka kakhulu. Ekuphenduleni kwe-fluorescent, ukuphuma kokukhanya kwenzeka ngokushesha futhi kubonakala kuphela ngenkathi umthombo wokukhanya uhlala usebenza (njengamalambu e-ultraviolet).
Ngokuphambene, ukusabela kwe-phosphorescent kuvumela okokusebenza ukuthi kugcine amandla amuncwa, okuwavumela ukuthi akhiphe ukukhanya kamuva, okuholela ekukhanyeni okuqhubekayo ngisho nangemva kokuba umthombo wokukhanya ucishiwe. Ngakho-ke, uma i-luminescence inyamalala ngokushesha, ihlukaniswa njenge-fluorescence; Uma iphikelela, ibonakala njenge-phosphorescence; futhi uma idinga ukusabela kwamakhemikhali ukuze isebenze, ibizwa nge-chemiluminescence.
Isibonelo, umuntu angacabanga nge-nightclub lapho indwangu namazinyo ekhipha ukukhanya okukhanyayo ngaphansi kokukhanya okumnyama (i-fluorescence), isibonakaliso sokuphuma esiphuthumayo sikhipha ukukhanya (i-phosphorescence), futhi izinti ezikhanyayo nazo zikhiqiza ukukhanya (chemiluminescence).
I-Fluorescence
Izinto ezikhipha ukukhanya ngokushesha zibizwa nge-fluorescent. Kulezi zinto, ama-athomu amunca amandla, abangele ukuthi bangene esimweni "sokuthokoza". Lapho zibuyela esimweni sazo esivamile cishe engxenyeni eyizinkulungwane eziyikhulu yomzuzwana (kusukela kumasekhondi angu-10-9 kuya kwangu-10-6), zikhulula la mandla ngendlela yezinhlayiya ezincane zokukhanya ezaziwa ngokuthi ama-photon.
Ngikhuluma ngokusemthethweni, I-Fluorescence inqubo yokukhipha imisebe lapho ama-electron ajabulile asuka endaweni ephansi kakhulu yenjabulo (S1) aye endaweni ephansi (S0). Phakathi nalolu shintsho, i-electron ikhipha ingxenye yamandla ayo ngokukhululeka kokudlidliza, okuholela ekutheni i-photon ekhishiwe ibe namandla ancishisiwe, ngenxa yalokho, ubude begagasi bude.
I-Phosphorescence
Ukuze uqonde umehluko phakathi kwe-fluorescence ne-phosphorescence, kuyadingeka ukuhlola kafushane umqondo we-electron spin. I-Spin imele isici esiyisisekelo se-electron, esebenza njengohlobo lomfutho we-angular onomthelela ekuziphatheni kwayo ngaphakathi kwenkambu ye-electromagnetic. Lesi sakhiwo singathatha kuphela inani elingu-½ futhi singabonisa umumo wokuya phezulu noma phansi. Ngenxa yalokho, ukujikeleza kwe-electron kuchazwa ngokuthi +½ noma -½, noma ngenye indlela imelelwa ngokuthi ↑ noma ↓. Ngaphakathi kwe-orbital efanayo ye-athomu, ama-electron ahlala ebonisa ukujikeleza kwe-antiparallel lapho esesimweni esiphansi se-singlet (S0). Ngemva kokunyuselwa esimweni sokujabula, i-electron igcina i-spin orientation yayo, okuholela ekwakhekeni kwesimo se-singlet ejabulile (S1), lapho kokubili ukuma kwe-spin kuhlala kumataniswe ekucushweni kwe-antiparallel. Kubalulekile ukuqaphela ukuthi zonke izinqubo zokuphumula ezihlotshaniswa ne-fluorescence ziyi-spin-neutral, okuqinisekisa ukuthi i-electron spin orientation iyalondolozwa ngaso sonke isikhathi.
Endabeni ye-phosphorescence, Inqubo ihluke kakhulu. Izinguquko ezisheshayo (ezisuka ku-10^-11 kuye ku-10^-6 amasekhondi) zenzeka phakathi kwamasistimu asuka kusimo senjabulo ye-singlett (S1) aye kusimo senjabulo ye-triplet (T1) esivuna ngamandla kakhudlwana. Lolu shintsho luholela ekuguqulweni kwe-electron spin; Izimo eziwumphumela zibonakala ngama-parallel spins kuwo womabili ama-electron futhi ahlukaniswa njengama-metastable. Kulesi simo, ukuphumula kwenzeka nge-phosphorescence, okuholela kokunye ukuguqulwa kwe-electron spin kanye nokukhishwa okulandelayo kwe-photon.
Inguquko ebuyela esimweni esikhululekile se-singlet (S0) ingenzeka ngemva kokulibaziseka isikhathi eside (okusukela ku-10^-3 kuya kumasekhondi angaphezu kuka-100). Phakathi nale nqubo yokuphumula, izindlela ezingasebenzisi imisebe zisebenzisa amandla engeziwe ekuphumuleni kwe-phosphorescent uma kuqhathaniswa ne-fluorescence, okuholela kumehluko omkhulu wamandla phakathi kwama-photons amuncwa nakhishiwe futhi ngenxa yalokho kube noshintsho olukhulu lobude.
I-Excitation kanye ne-emission spectra
I-Luminescence yenzeka lapho ama-electron ento ejatshuliswa ukumunca ama-photon, bese ekhipha lawo mandla ngendlela yemisebe. Kwezinye izimo, Imisebe ekhishiwe ingaba nama-photon anamandla afanayo nobude begagasi njengalawo amuncwa; Lesi simo saziwa ngokuthi i-resonance fluorescence. Imvamisa, imisebe ekhishwayo inobude begagasi ende, okubonisa amandla aphansi uma kuqhathaniswa nama-photon amuncwa.
Lokhu kushintshela kumaza amade amaza kwaziwa ngokuthi iStokes shift. Lapho ama-electron ejatshuliswa imisebe emifushane, engabonakali, akhuphukela ezifundeni zamandla aphezulu. Lapho zibuyela esimweni sazo sasekuqaleni, zikhipha ukukhanya okubonakalayo okunobude beza obufanayo, okuyisibonelo se-resonance fluorescence. Kodwa-ke, lawa ma-electron ajabulile angaphinde abuyele ezingeni lamandla elimaphakathi, okuholela ekukhishweni kwe-photon ekhanyayo ethwala amandla amancane kunalawo esasasa lokuqala. Lolu hlelo, lapho ibangelwa ukukhanya kwe-ultraviolet, ngokuvamile ibonakala njenge-fluorescence ngaphakathi kwe-spectrum ebonakalayo. Esimeni sezinto ze-phosphorescent, kukhona ukubambezeleka phakathi kwe-excitation yama-electron kumazinga aphezulu wamandla kanye nokubuyela kwawo esimweni esiphansi.
Into ethile ayiphenduli kuwo wonke amaza wamaza. Kodwa-ke, kuvame ukuhlobana phakathi kobude begagasi besasasa kanye ne-amplitude yokukhishwa okuwumphumela. Lobu budlelwano baziwa ngokuthi i-excitation spectrum. Ngokufanayo, Ukuhlobana kungabonwa phakathi kwe-amplitude nobude begagasi bemisebe ekhishwayo, eyaziwa ngokuthi i-spectrum ephumayo.
Kubalulekile ukuqaphela ukuthi i-wavelength ekhishwayo ayincikile kubude begagasi benjabulo, ngaphandle kwasezimeni lapho izinto zinezinto eziningi ze-luminescence. Ngenxa yalokho, amaminerali abonisa amakhono ahlukene okumunca ukukhanya kwe-ultraviolet kumaza athile; amanye ama-fluoresce ngaphansi kokukhanya kwe-ultraviolet amaza amafushane, kanti amanye akhanya ngaphansi kwamaza amade amade, kanti amanye abonisa i-fluorescence engacacile. Umbala wokukhanya okukhiphayo uvame ukuhluka kakhulu ngamaza amaza okuvusa ahlukahlukene.
Ukwenzeka kwalezi zenzakalo akugcini nje ekusebenziseni imisebe ye-ultraviolet; kunalokho, ukuvusa amadlingozi kungafinyelelwa nganoma yimiphi imisebe enamandla afanele. Ngokwesibonelo, Ama-X-ray ayakwazi ukunxenxa i-fluorescence ezintweni ezihlukahlukene, eziningi zazo ezisabela ezinhlotsheni ezahlukene zemisebe. I-Magnesium tungstate, isibonelo, ibonisa ukuzwela cishe kuyo yonke imisebe enamaza amaza angaphansi kuka-300 nm, ehlanganisa i-ultraviolet ne-X-ray spectrum Ukwengeza, izinto ezithile zingajatshuliswa ama-electron, njengoba kuboniswa amashubhu kamabonakude.
Ngithemba ukuthi ngalolu lwazi ungafunda kabanzi mayelana nomehluko phakathi kwe-fluorescence, i-phosphorescence kanye ne-luminescence.