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) 2308. [3]F. Lahmani, C. Lardeux, D. Solgadi, Chem. Phys. Lett. 129 (1986) 24. [4]P. Andresen, et al. J. Chem. Phys. 110 (1999) 4777.  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. 0 16 30 20 10 0 -10 17.8 -8 BrCH 2 CH 2 O ‧ CH 2 Br ‧ + CH 2 O CH 2 =CHO ‧ +HBr 21 40 9 BrCH 2 CHO ‧ + H E T (kcal/mol) Figure : G4//B3LYP/6-311++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/6-311++g(3df,2p) Calculations on the Dissociation of BrCH 2 CH 2 ONO 17 CH 2 =CHONO CH 2 =CH 2 O ‧ + ‧ NO 30 20 10 0 -10 E T (kcal/mol) HBr+ CH 2 =CHONOBrCH 2 CH 2 ONO

6. 81.539 13.5 2.84 hv Unit: kcal/mol

7. 0 16 30 20 10 0 -10 17.8 -8 BrCH 2 CH 2 O ‧ CH 2 Br ‧ + CH 2 O CH 2 =CHO ‧ +HBr 21 40 9 BrCH 2 CHO ‧ + H E T (kcal/mol) Figure : G4//B3LYP/6-311++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 82 30  29 30 42 93 43  42 CH 2 =CHO ‧ + HBr m/z=29 、 30 、 42 、 79 、 82 、 93 m/z=123 、 122 H+ BrCH 2 CHO 123 122 X ?

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

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