Presentation is loading. Please wait.

Presentation is loading. Please wait.

Photodissociation Dynamics of 2-Bromoethylnitrite at 351 nm and C-C Bond Fission in the Bromoethoxy Radical Product Lei Wang Laurie Butler Group University.

Similar presentations


Presentation on theme: "Photodissociation Dynamics of 2-Bromoethylnitrite at 351 nm and C-C Bond Fission in the Bromoethoxy Radical Product Lei Wang Laurie Butler Group University."— Presentation transcript:

1 Photodissociation Dynamics of 2-Bromoethylnitrite at 351 nm and C-C Bond Fission in the Bromoethoxy Radical Product Lei Wang Laurie Butler Group University of Chicago

2 Introduction atmospheric ozone levels [1] photochemical smog  Studies on nitrous acid (HONO) [2], methyl nitrite(CH 3 ONO) [3] and t-butyl nitrite ((CH 3 ) 3 CONO) [4] previously [1]wikipedia [2]R.N. Dixon, H. Rieley, J. Chem. Phys. 91 (1989) [3]F. Lahmani, C. Lardeux, D. Solgadi, Chem. Phys. Lett. 129 (1986) 24. [4]P. Andresen, et al. J. Chem. Phys. 110 (1999)  Halogenated alkyl nitrites are quite different from the well studied alkyl nitrite

3 351nm Br ‧ + ‧ CH 2 CH 2 ONO BrCH 2 CH 2 ONO HBr+ CH 2 =CHONO BrCH 2 CH 2 O ‧ + ‧ NO BrCH 2 CH 2 ONO

4 BrCH 2 CH 2 O ‧ CH 2 Br ‧ + CH 2 O CH 2 =CHO ‧ +HBr BrCH 2 CHO ‧ + H E T (kcal/mol) Figure : G4//B3LYP/ g(3df,2p) Calculations on the Dissociation of BrCH 2 CH 2 ONO BrCH 2 CH 2 ONO BrCH 2 CH 2 O ‧ + ‧ NO

5 0 21 Figure : G4//B3LYP/ g(3df,2p) Calculations on the Dissociation of BrCH 2 CH 2 ONO 17 CH 2 =CHONO CH 2 =CH 2 O ‧ + ‧ NO E T (kcal/mol) HBr+ CH 2 =CHONOBrCH 2 CH 2 ONO

6 hv Unit: kcal/mol

7 BrCH 2 CH 2 O ‧ CH 2 Br ‧ + CH 2 O CH 2 =CHO ‧ +HBr BrCH 2 CHO ‧ + H E T (kcal/mol) Figure : G4//B3LYP/ g(3df,2p) Calculations on the Dissociation of BrCH 2 CH 2 ONO

8 351nm photon 200 eV Electron bombardment ionizer Ion lensesQuadruple MS Doorknob PMT Scintillator nozzle skimmers 10° Experimental Method

9 BrCH 2 CH 2 OCH 2 Br+BrCH 2 CH 2 ONO 351nm photon 200 eV Electron bombardment ionizer Ion lensesQuadruple MS Doorknob PMT Scintillator nozzle skimmers 10° BrCH 2 CH 2 O  BrCH 2 CH 2 O +  CH 2 Br+ BrCH 2 CH 2 O  CH 2 Br + CH 2 O  CH 2 Br+ Cracking Secondary Cracking Secondary BrCH 2 CH 2 ONO CH 2 Br+ BrCH 2 Neutral flight timeIon flight time

10 Results and Analysis BrCH 2 CH 2 ONO HBr + CH 2 =CHONO ‧ NO + BrCH 2 CH 2 O ‧ CH 2 =CHO ‧ + ‧ NO CH 2 Br ‧ + CH 2 O   42 CH 2 =CHO ‧ + HBr m/z=29 、 30 、 42 、 79 、 82 、 93 m/z=123 、 122 H+ BrCH 2 CHO X ?

11 ‧ NO + BrCH 2 CH 2 O ‧ CH 2 Br ‧ + CH 2 O BrCH 2 CH 2 ONO CH 2 Br +, CHO+

12

13 BrCH 2 CH 2 ONO ‧ NO + BrCH 2 CH 2 O ‧ CH 2 Br + CH 2 O ‧ Summary & Future work  Only the O-NO bond fission channel forming the bromoethoxy radical and NO  No HBr photoelimination  The subsequent decomposition to formaldehyde+ CH 2 Br was also investigated  Vinoxy radical needs to be further proved CH 2 =CHO ‧ + HBr ?

14 Acknowledgement Butler Group  Prof. Laurie Butler  Martin Lam  Matt Brynteson  Ryan Booth  Carrie Womack Miller Group  Prof. Terry Miller  Rabi Chhantyal Pun


Download ppt "Photodissociation Dynamics of 2-Bromoethylnitrite at 351 nm and C-C Bond Fission in the Bromoethoxy Radical Product Lei Wang Laurie Butler Group University."

Similar presentations


Ads by Google