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Photochemistry can be dramatically different from “ordinary” chemistry See example below

Photochemistry can be dramatically different from “ordinary” chemistry See example below. Cl. Cl. Ar. Ljósefnafræði ; Dæmi / photochemistry example:. Cl. Cl. Ar. Ljósefnafræði ; Dæmi / photochemistry example:. . . . Cl. Cl. Ar. Ljósefnafræði ; Dæmi / photochemistry example:.

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Photochemistry can be dramatically different from “ordinary” chemistry See example below

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  1. Photochemistry can be dramatically different from “ordinary” chemistry See example below

  2. Cl Cl Ar Ljósefnafræði ; Dæmi / photochemistry example:

  3. Cl Cl Ar Ljósefnafræði ; Dæmi / photochemistry example: . . .

  4. Cl Cl Ar Ljósefnafræði ; Dæmi / photochemistry example:

  5. - + Cl Ar Ljósefnafræði ; Dæmi / photochemistry example: Cl

  6. Cl Ar Ljósefnafræði ; Dæmi / photochemistry example: Cl

  7. Ljósmyndun efnahvarfa; Nóbelsverðlaunin í efnafræði, 1999 * Sjá: http://www.hi.is/~agust/ * Sjá: http://www.hi.is/~agust/

  8. Hr.efnahv. Gangur og hraði efnahvarfa: A + BC + D

  9. Hr.efnahv. Arrheníus: Nóbelsverðlaun 1903 Ljósmyndun efnahvarfa; Nóbelsverðlaunin í efnafræði, 1999 Gangur og hraði efnahvarfa: A + BC + D Hraði = k[A][B]; k = Aexp(-Ea/RT); k <= [A] vs t mælingar Hr.efnahv.

  10. 1930-1940: Kenning um skammlíft milliástand: Kenning Henry Eyring Michael Polanyi # A..B 1 2 A + B C + D # Skammlíft milliástand: Líftími »tími tengjasveiflu, dæmigert 10-13 – 10-12 sek 1: 2:

  11. John C. Polanyi Nóbelsverðlaun, 1986: Dudley Herzbach Yuan Lee 1975-1990: Tilraunir með sameindabunur: Bunur Sameinda- buna Árekstur Skynjun myndefna/ hvarfefna Hreyfanlegur skynjari -Ráðið í eiginleika milliástanda út frá dreifingu / endurkasti sameinda

  12. “Femtósekúndu litrófsgreining” Nóbelsverðlaunin í efnafræði 1999: Próf. Ahmed Zewail, Caltech. 1985 - “Ljósmyndun efnahvarfa” Ljosm. Þ.e. Gleypnimælingar milliástanda vs tími fyrir tíma(bil) £10-12 s: Gleypnimælingar með ljósleiftrum 10-15 s AB CD A . .B C ..D A + B 0,000000000000001 s C + D

  13. Verðl.

  14. http://www.its.caltech.edu/~femto/ Femtol.

  15. Of margbreytilegt /flókið Hvernig / Hvað? Hvernig? A + BC + D Öll stig hvarfsins koma fyrir samtímis, þ.e.:

  16. Dæmi: “½ hvarf”, sbr.: ICN# I + CN, Þ.e.: I CN# Skapa þarf “samhæfðar aðstæður”:

  17. Dæmi: “½ hvarf”, sbr.: ICN# I + CN, Þ.e.: Gleypnimælingar ICN# I +CN ICN# Myndað með femtó- sekúndu LASER-púls gleypni ICN Skapa þarf “samhæfðar aðstæður”: ½ hvarf I CN

  18. Framkvæmd: ICN-Tilr.

  19. Gleypni- Mælingar: Niðurstöður: Nánar: ICN# I +CN ICN-niðurst. ICN

  20. (a) (b) [NaI#Na..I# ]Na + I NaI NaI (a) NaI# (b) Na

  21. Stilbene(1)

  22. Stilbene(2)

  23. IH..OCO [I..H..O..CO]I+HO+CO IH+OCO Van der Waals “Sameindir” Spýtt- kæling Sameinda- buna

  24. Cyclob. C4H8C4H8#C2H4 + C2H4 ???

  25. Rofnun tetrafluordijoðetans: C2F4I2 C2F4I2C2F4 + 2I: . I F I F F ?(1) F C C C C F . F F I F I . I F F I F I F F . F ?(2) C C C C C C . F . F F I F I F F I

  26. mynataka

  27. 5

  28. 6

  29. 7

  30. 8

  31. 9

  32. 10

  33. Reactioncrosssection: A + M ??? M1 + M2 ??? A + B C + D

  34. Cross section = s = <d>2p Reactioncrosssection: A + M ??? M1 + M2 ??? A + B C + D d But ions:

  35. + + - - - + - + + + F µ 1/r2 But ions: Reactioncrosssection: A+ + B C + D

  36. + + - - - + - + + + But Ions: Reactioncrosssection: A+ + B C + D

  37. + + But ions: Reactioncrosssection: A+ + B C + D Collision frequency much larger

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