We have theoretically studied the nonadiabatic transitions among the five lower states with the Ω=1u symmetry (1u(1) to 1u(5)) in the photodissociation of Cl2, Br2, and I2 by using the spin-orbit configuration interaction (SOCI) method and the semiclassical time-dependent coupled Schrödinger equations. From the configuration analyses of the SOCI wavefunctions, we found that the nonadiabatic transition between 1u(2) and 1u(1) is a noncrossing type, while that between 1u(3) and 1u(4) is a crossing type for all the molecules. The behavior of the radial derivative coupling element between 1u(1) and 1u(2) and that between 1u(3) and 1u(4) is analyzed in detail. In Cl2, nonadiabatic transitions can take place even between the states correlating to different dissociation limits, while in Br2 and I2, with the usual photon energies e.g. less than 20 eV, nonadiabatic transitions occur only between the states correlating to the same dissociation limits, reflecting the different magnitudes of the spin-orbit interactions.
ASJC Scopus subject areas
- 化学 (全般)