Schematic description of the dissociation channels Br 3Pj H 2S

Meg (in atomic units, IDebye = 0.3935 a.u.) is the electronic transition matrix element between the e and g electronic states, assuming the dipole length approximation, (ve is the energy normalized nuclear continuum wavefunction, and fj) is the initial state bound vibrational wavefunction. The overlap integral has units of cm1/2 (see Section 7.5). Note that 10 18 cm2=lMb 

The theoretical cross section, r(E), must be convoluted with the experimental resolution before being compared to the experimental cross section. 

Above the ionization threshold (see Chapter 8), the absolute photodissociation cross section can be obtained as the difference between the absolute total absorption cross section and the absolute photoionization cross section (see for example, for N2, Fig. 6 of Shaw, et ai, 1992). Another experimental quantity is the ionization efficiency defined as the total photoionization cross section divided by the total absorption cross section. 

In order to compute or interpret photodissociation a(E) functions, it is necessary to know (i) the potential energy curve of the initial state (ii) the potential energy curves of all energetically accessible excited electronic states (both purely repulsive states and the above dissociation repulsive region of bound states) (iii) the electric dipole transition moment function between the initial and final state (iv) the (R- dependent) interactions among the set of electronic 

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Figure 7.2 Schematic description of the dissociation channels Br+(3Pj) + H(2S) for the molecular states X2IIj (configuration a2it3 at Re), 4S and 2E (

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