1. CH 2 Br 2 : 1)IE (ionization energy) 2)Laser induced photodissociation and ionization 3)Papers 4) Energetics agust,www,…ch2br2/PPT-010211ak.ppt agust,heima,….CH2Br2/XLS-030211ak.xls agust,heima,…CH2Br2/PXP-030211ak.pxp

2. NIST:

4. 2) Chemical Physics Letters Volume 382, Issues 5-62) Chemical Physics Letters Volume 382, Issues 5-6, 15 December 2003, Pages 637-643 (see cpl382- 637-03.pdf): http://www3.hi.is/~agust/rannsoknir/papers/CH2X2/cpl382-637-03.pdf Laser induced photodissociation of CH 2 Cl 2 and CH 2 Br 2 at 355 nm: an experimental and theoretical study P. Sharma a, R. K. Vatsa a, D. K. Maity b and S. K. Kulshreshtha a b Abstract Experimental and theoretical studies have been carried out for nanosecond 355 nm laser induced dissociation/ionisation of dihalomethanes (CH 2 Cl 2 and CH 2 Br 2 ) using time of flight mass spectrometer. Both the molecules follow quite similar ionisation pattern and mass spectra showed H +, CH 2 +, X +, CX +, and CH 2 X + as major ions with absence of parent ion peak. The energetics of different dissociation channels in the ground state of CH 2 X + /CH 2 X systems was investigated using ab initio calculations. Proposed mechanism involves dissociation of CH 2 X 2 into CH 2 X, which then dissociates into several distinct competitive channels, products of which are subsequently ionised.

5. 3) Important papers a) Absorption spectra / absorption cross sections (Molina): http://notendur.hi.is/agust/rannsoknir/papers/jpc86-2672-82.pdf b) Phototdissoziations and ionizations: http://www3.hi.is/~agust/rannsoknir/papers/CH2X2/cpl382-637-03.pdf http://www3.hi.is/~agust/rannsoknir/papers/CH2X2/cpl382-637-03.pdf c)

6. 4) CH2Br2 energetics error limitsref: IE10.41eV0.13eV83962.28cm-1NIST BrH2C-Br bond energy3.06eV24680.56cm-1http://www3.hi.is/~agust/rannsoknir/papers/CH2X2/cpl382-637-03.pdf CH2Br->CH2 + Br77.6kcal/mol27140.99cm-1http://www3.hi.is/~agust/rannsoknir/papers/CH2X2/cpl382-637-03.pdf BrH2C + Br24680.56cm-1 CH2 + Br + Br51821.55cm-1 IP(Br)95284.8cm-1 BrH2C + Br + e-119965.4cm-1 IP(CH2Br)8.61eV69444.31cm-1 BrH2C+ + Br+e-94124.86cm-1 f1:8065.541cm-1/eV f2:349.755cm-1/kcalmol-1 agust,heima,….CH2Br2/XLS-030211ak.xls

7. CH 2 Br 2 + + e-; 83962.28 cm -1 CH 2 Br + Br; 24680.56 cm-1 CH 2 + Br + Br; 51821.55 cm-1 CH 2 Br + Br + +e-; 119965.4cm-1 CH 2 Br + + e- + Br; 94124.86 cm-1 agust,heima,…CH2Br2/PXP-030211ak.pxp; Lay:0, Gr:0; 70000 cm -1 (1) (2) (3) (4) (total number of photons =2+n)

8. CH 2 Br 2 + + e-; 83962.28 cm -1 CH 2 Br + Br; 24680.56 cm -1 CH 2 + Br + Br; 51821.55 cm -1 CH 2 Br + Br + +e - ; 119965.4cm-1 CH 2 Br + + e - + Br; 94124.86 cm -1 agust,heima,…CH2Br2/PXP-030211ak.pxp; Lay:0, Gr:0; 70000 cm -1 2 x 28169= 56338 cm -1 (355 nm 1) ) 1) http://www3.hi.is/~agust/rannsoknir/papers/CH2X2/cpl382-637-03.pdf http://www3.hi.is/~agust/rannsoknir/papers/CH2X2/cpl382-637-03.pdf

9. Bond dissociation energy: (fundið á netinu;) D(CH-H): 37115.50 cm -1 D(C-H): 28338.19 cm -1 D(H 2 ): 38202.22 cm -1 D(HBr): 30595.21 cm -1 D(Br 2 ): 24158.51 cm -1 CH 2 + Br + Br = 51821.55 cm -1 (skv. mynd í power point skalinu sem þú sendir mér) (CH 2 + Br + Br) + D(CH-H) + D(C-H) = H + H + C + Br + Br: 51821,55 cm -1 + 37115,50 cm -1 + 28338,19 cm -1 = 117275,24 cm -1 (H + H + C + Br + Br) – D(Br 2 ) = H+H+C+Br2 117275,24 cm -1 – 24158,51 cm -1 = 93116.73 cm-1 (H + H + C + Br + Br) – D(HBr) = H + Br + C + HBr 117275.24 cm -1 – 30595.21 cm -1 = 86680.03 cm -1 (H + H + C + Br + Br) – D(H 2 ) = H2 + C + Br + Br 117275,24 cm -1 – 38202,22 cm -1 = 79073.02 cm-1 (H + H + C + Br + Br) – 2D(HBr) = HBr + C + HBr 117275,24 cm -1 – 2 ∙ 30595,21 cm -1 = 56084,82 cm -1 (H + H + C + Br + Br) – D(Br 2 ) – D(H 2 ) = H 2 + C + Br 2 117275,24 cm -1 – 24158,51 cm -1 – 38202,22 cm -1 = 54914,51 cm -1 Samantekt: H + H + C + Br + Br: 117275.24 cm -1 H+H+C+Br 2 = 93116.73 cm -1 H + Br + C + HBr = 86680.03 cm -1 H 2 + C + Br + Br = 79073.02 cm -1 HBr + C + HBr: 56084.82 cm -1 H 2 + C + Br 2 : 54914.51 cm -1 HII & AK:

10. CH 2 Br 2 + + e-; 83962.28 cm -1 CH 2 Br + Br; 24680.56 cm -1 CH 2 + Br + Br; 51821.55 cm -1 CH 2 Br + Br + +e - ; 119965.4cm-1 CH 2 Br + + e - + Br; 94124.86 cm -1 agust,heima,…CH2Br2/PXP-030211ak.pxp; Lay:0, Gr:0; update: 080311 70000 cm -1 2 x 28169= 56338 cm -1 (355 nm 1) ) 1) http://www3.hi.is/~agust/rannsoknir/papers/CH2X2/cpl382-637-03.pdf http://www3.hi.is/~agust/rannsoknir/papers/CH2X2/cpl382-637-03.pdf H 2 + C+ Br 2 ; 54914.51 cm -1 2HBr+ C; 56084.82 cm -1 H 2 + C+2Br; 79073.02 cm -1 H+Br+ C+HBr; 86680.03 cm -1 2H+ C+Br 2 ; 93116.73 cm -1 2H+ C+2Br; 117275 cm -1 Neutral species:

11. Heimild I: Morrison, R. T. „Organic Chemistry“ http://www.archive.org/stream/organicchemistry031426mbp/organicchemistry031426mbp_djvu.txthttp://www.archive.org/stream/organicchemistry031426mbp/organicchemistry031426mbp_djvu.txt sett inn: 2005 D(CH-H): 106 kcal/mól = 37115,50 cm -1 D(C-H): 81 kcal/mól = 28338,19 cm -1 D(H-Br): 88 kcal/mól = 30762,40 cm -1 D(H-H): 104 kcal/mól = 36413,32 cm -1 D(Br-Br): 46 kcal/mól = 16108,46 cm -1 CH 2 + Br + Br = 51821,55 cm -1 (skv. mynd í power point skalinu sem þú sendir mér) (CH 2 + Br + Br) + D(CH-H) + D(C-H) = H + H + C + Br + Br: 51821,55 cm -1 + 37115,50 cm -1 + 28338,19 cm -1 = 117275,24 cm -1 (H + H + C + Br + Br) – 2D(H-Br) = HBr + C + HBr 117275,24 cm -1 – 2 ∙ 30762,40 cm -1 = 55750,44 cm -1 (H + H + C + Br + Br) – D(Br-Br) – D(H-H) = H 2 + C + Br 2 117275,24 cm -1 – 16108,46 cm -1 – 36413,32 cm -1 = 64753,46 cm -1 (H + H + C + Br + Br) – D(Br-Br) = H + H + C + Br 2 117275,24 cm -1 – 16108,46 cm -1 = 101166,78 cm -1 (H + H + C + Br + Br) – D(H-Br) = H + Br + C + HBr 117275,24 cm -1 - 30762,40 cm -1 = 86512,84 cm -1 (H + H + C + Br + Br) – D(H-H) = H 2 + C + Br + Br 117275,24 cm -1 – 36413,32 cm -1 = 80861,92 cm -1 Samantekt: H + H + C + Br + Br = 117275,24 cm -1 H + H + C + Br 2 = 101166,78 cm -1 H + Br + C + HBr = 86512,84 cm -1 H 2 + C + Br + Br = 80861,92 cm -1 H 2 + C + Br 2 = 64753,46 cm -1 HBr + C + HBr = 55750,44 cm -1 Agust,heima,....CH2Br2/Tengiorka-090311hii.doc HII: