1. 1 CH3Br, 161109 C, C* and C** dissociation formation channels vs C+ spectra Explanation for enhanced C+ Rydberg state spectra in the 80600 - 80950 cm-1 region Agust,heima,...Nov09/CH3Br-Overall +mass-041109km-141109ak.pxp Agust,www,.... Nov09/PPT-161109ak.ppt

2. 2 Agust,heima,...Nov09/CH3Br-Overall +mass-041109km-141109ak.pxp: Predictions 2s 2 2p4p( 1 D 2 ): 71577.2 2s 2 2p4p( 1 S 0 ): 72059.1 2s 2 2p5p: 2s 2 2p6p: H 2 + C + HBr H 2 + C* + HBr ATH! 2hv

3. 3 (1/2)4f;1 (1/2)4f;0+ (3/2)5f;1/0 (3/2)6d;0(1/2)5d;0 (3/2)6d;2(1/2)5d;2 (3/2)6d;0 (1/2)5d;0 (1/2)4f;1 (1/2)4f;0+ (3/2)5f;1/0 agust, heima,....Nov09/CH3Br-Overall +mass-041109km-121109ak.pxp : C+

4. 4 We observe enhanced Rydberg state structure in the spectra region 80600 - 80950 cm-1 by recording C+. This could be for two reasons: 1) -because we switch from three photon ionization of C*(1D) (formed after dissociation of CH3Br*(Rydberg state) to form H2 + C*(1D) + HBr) to two photon ionization. or 2) formation of C**(2s22p2; 1S) due to opening of yet another dissociation channel: CH3Br* -> H2 + C**(2s22p2; 1S) + HBr See relevant energetics in next slides:

5. 5 80600 cm -1 40300 CH 3 Br 10k 40k 70k CH 3 Br* C*( 1 D 2 )+H 2 +HBr ca 70000 C**( 1 D 2 )+H 2 +HBr 130k 150k C + +H 2 +HBr+ e - Ca = 70000 + 80625.27= 150625 cm-1 80k C ( 3 P J )+ H 2 +HBr ca < 60000(?) 10192.63 (NIST) IP(C) = 90817.9 (see notes 240809;1)& http://www.nist.gov/srd/nsrds/NSRDS-NBS34.pdf 90817.9 -10192.63= 80625.27 cm-1 1)

6. 6 80600 cm -1 40300 CH 3 Br 10k 40k 70k CH 3 Br* C*( 1 D 2 )+H 2 +HBr ca 69144.63 C**( 1 D 2 )+H 2 +HBr 130k 150k C + +H 2 +HBr+ e - Ca = 69169.89 + 80600= 149770 cm-1 80k C ( 3 P J )+ H 2 +HBr ca 58952(?) 10192.63 (NIST) IP(C) = 90817.9 (see notes 240809;1)& http://www.nist.gov/srd/nsrds/NSRDS-NBS34.pdf 90817.9 -21648.01= 69169.89 cm-1 2) (alternatively) C*( 1 S)+H 2 +HBr ca 80600 21 648.01 (NIST) NB: AB comes up with a value of 704 kJ Mol-1 / 58840 cm-1 704 = 0+711.19-28.6-(-21.3) for 0 K (e-mail: 041109) I obtain 709.7 kJmol-1/59329 cm-1 for DE obtained for DHf standard values (see http://www3.hi.is/~agust/rannsoknir/rempi/ch3br/Nov09/PPT-151109ak.ppt ) http://www3.hi.is/~agust/rannsoknir/rempi/ch3br/Nov09/PPT-151109ak.ppt