WAVEPACKET DYNAMICS IN 5 DIMENSIONS - PHOTODISSOCIATION OF METHYL-IODIDE

To demonstrate the applicability of the multiconfigurational time-dependent Hartree (MCTDH) approach to higher-dimensional problems, the photodissociation dynamics of methyl iodide is investigated. A fully quantum-mechanical description is employed which includes as many as five vibrational degrees of freedom and three electronic states. Convergence of the calculations with respect to the number of configurations is demonstrated. Nonorthogonal bond length and bond angle coordinates are used, allowing for the more intuitive description desirable for complex polyatomic systems. A pseudospectral implementation of MCTDH, employing a complicated kinetic energy operator corresponding to such coordinates, removes the restriction to simplified models used in earlier studies. Results are compared with previous theoretical descriptions and experimental findings. The absorption spectrum is given and important correlations amongst the different degrees of freedom and their relevance to the photodissociative process are discussed.