1. CH3Br, 051109 Relative ion signals (I(M + )/I(CH 3 + )) vs Rydberg states agust,www,....Nov09/PPT-051109ak.ppt agust,heima,...CH3Br-Overall +mass-041109km-051109ak.pxp agust,heima,....XLS051109ak.xls NB: background spectra have not been subtracted in the mass spectra shown below

2. CH 3 + 2hv CH 3 + + Br - / Threshold 76695 cm -1 Mw C + (partly due to impurities)

3. 2hv CH 3 + + Br - / Threshold 76695 cm -1 Mw CH 3 + C + (partly due to impurities) 66022 66503 67275 68675 68882 75395 75887 76672 77165 77841 78393 78410 79195 79594

4. 2hv CBr + Br + Mw CH 3 + + Br - / Threshold 76695 cm -1 See below 66022 66503 67275 68675 68882 75395 75887 76672 77165 77841 78410

5. NB: relative ion signals (I(M + ) rel ) above are I(M + )/I(CH 3 + ) I(CH n + ) rel ; n = 2,1 and I(Br + ) rel increase as energy increases from 66000cm -1 to the CH 3 + + Br - threshold (76695 cm -1 ) I(CH n + ) rel ; n = 2,1 and I(Br + ) rel decrease as energy increases above 76695cm -1 I(Br + )rel vanishes for energies above about 78400. I(CBr + ) rel stays almost constant for all energies, 66000 – 78400 after which it vanishes. Now lets check background signals vs Rydberg state signals:

6. CH 3 + CBr + Br + Background Near 77542.2 Rydb. state 77841 agust,heima,...CH3Br-Overall +mass-041109km-051109ak.pxp : Above Threshold:

7. CH 3 + CBr + Br + Background Near 77542.2 Rydb. state 77165 agust,heima,...CH3Br-Overall +mass-041109km-051109ak.pxp : Above Threshold:

8. It actually looks as if I(Br+) rel, I(CBr+) rel and I(CHn+) rel ; n = 2,1 are slighly stronger for the “background signal” compared to the “neighbour” (Rydberg + bgr)-signals. Lets check more bgr signals:

9. CH 3 + CBr + Br + Background Near 79324 Rydb. state 78410 Rydb. state 79594 agust,heima,...CH3Br-Overall +mass-041109km-051109ak.pxp : Way above Threshold:

10. Comparable I(M+) signals are seen for Rydberg (+bgr) and background signals!

11. CH 3 + Near threshold

12. It actually looks as if I(Br+) rel, only are slighly stronger for the “background signal” compared to the “neighbour” (Rydberg + bgr)-signal. Now we need to go below threshold