Things to address in our CH 3 Br studies / publication(s)

1. Things to address in our CH3Br studies / publication(s) • Main reference is T. Ridley et al., JPC A, 112, 7170, (2008):http://www3.hi.is/~agust/rannsoknir/papers/jpcA112-7170-08.pdf • Emphasize both CH379Br and CH381Br and make relevant comparison. • Spectra measurements (HRH & VHW): • record 2D REMPI / (2+n)REMPI spectra and focus on masses such as: • CH3: .............15 • 79Br+..............79 • 81Br+..............81 • CH379Br+........94 • CH381Br+....... 96 • -as a function of 2hn / cm-1 • emphasise to study ion signal as a function of Rydberg state (analogus to our • acetylene studies (http://www3.hi.is/~agust/rannsoknir/papers/cpl458-58-08.pdf ) • Record individual “Rydberg state spectra” to search for rotational structure or • structure profile.

2. T. Ridley et al., JPC A, 112, 7170, (2008):

3. T. Ridley et al., JPC A, 112, 7170, (2008): CH3+ + Br- formation limit 76695 cm-1 • Emphasize this region to start with:

4. Questions to address: • -do relative ion signals alter with laser wavenumbers / Rydberg states • in the region 66000 – 76700 cm-1; if so, how? • - is Rydberg state <-> ion-pair interaction altering with wavenumbers? • Analysis: • Derive I(N+)/I(CH3Br+); N+ = CH3, Br+ vs Rydberg state / wavenumbers • Present data as columns vs wavenumbers (2hn) (HRH) • Qualitative interpretation in terms of photorupture mechanisms. • Preparation work: • Make energy level diagrams (IN IGOR) for • - Rydberg state (HRH) • Br* + CH3 energies (HRH) • Estimate energies for ion-pair state (CH3+Br-) (ÁK) • Power dependence experiments (VHW, HRH): • I(N+) (N+ = CH3+, Br+ and CH3Br+) vs Power => ln(I) vs ln(P) => • determine number of photons (n) required • to ionize and/ or saturation effects