Quantum‐mechanical study of the I₂–Ne vibrational predissociation dynamics: A three‐dimensional time‐dependent self‐consistent‐field approach

A three‐dimensional time‐dependent self‐consistent‐field (TDSCF) approach is proposed to study the vibrational predissociation of the I₂(B)–Ne van der Waals (vdW) complex. Jacobian coordinates are used within the assumption of zero‐total angular momentum. In the method the total wave function is factorized such that the bending mode of the system is explicitly separated, while the coupling between the remaining two degrees of freedom is treated exactly. The decay dynamics of several resonances corresponding to different initial vibrational states of I₂ is investigated through long‐time wave packet propagations. Calculated resonance lifetimes are compared to experimental data and found to be in quantitative agreement with them. The results show that predissociation of the complex is mainly governed by the coupling between the I₂ and the vdW stretching vibrations, whereas the bending mode has a rather weak effect on the dynamics. The good quality of the TDSCF description of this long‐time dynamical process is due to the adaptation of the decoupling approximations applied in the method to the physical situation of the system. The validity of the approach is discussed in the light of the results.