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

Abstract

Articles you may be interested inA full-dimensional quantum approach to the vibrational predissociation of tetra-atomic complexes based on the partially-separable time-dependent self-consistent-field approximation J. Chem. Phys. 116, 6595 (2002) A three-dimensional time-dependent self-consistent-field ͑TDSCF͒ approach is proposed to study the vibrational predissociation of the I 2 (B) -Ne van der Waals ͑vdW͒ 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 I 2 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 I 2 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.

Rotational State Distributions of I2(B) from Vibrational Predissociation of I2(B)-Ne

“…It is found that the rotational state distributions of product I 2 through ∆v = −1 channel are notably different from those through ∆v = −2 channel. 14,24 But, here we do not present analyses on the distributions through higher channels because the ∆v = −2 or up channels do not contribute much to the total predissociation rate. The predissociation rates for ∆v = −2 are one or two orders of magnitude smaller than the ∆v = −1, and the ∆v = −3 rates are even smaller than the ∆v = −2.…”

“…Since the early stage of predissociation research, [3][4][5][6] the vibrational predissociation of I2(B)-Ne(in the excited 3 Π (0u + ) electronic state 7 ) has been most frequently investigated. [8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23][24] The first investigation by Levy's group measured predissociation rates and some excited vibrational energy levels of I2(B)-Ne. [3][4][5][6] The accurate vibrational predissociation rates (or lifetimes) of I2(B)-Ne(v1, 0, 0) were first reported by Zewail and coworkers.…”

“…20 Theoretical investigations on vibrational predissociation of I 2 (B)-Ne have also been carried out extensively. [13][14][15][16][17][18][19]21,24 The most widely used potential energy function is a pairwise sum of the potentials of diatomic I-I and of Ne-I. The I-I potential energy function is empirically determined from the Zewail's experiment.…”

Quasiclassical dynamics of the I2–Ne2 vibrational predissociation: A comparison with experiment

“…46 In the case of I 2 -Ne n clusters with nϾ1, the diatomic cromophore is coupled to dissociating modes and also to a number of nondissociating ''bath modes'' which increases with n, and may play an important role in the dynamics. In fact, the mechanism of cluster dissociation can be affected by these bath modes, potential acceptors of the I 2 vibrational energy.…”

“…[29][30][31][32] The appearance of time-domain experimental data, along with the development of techniques to solve efficiently the time-dependent Schödinger equation [33][34][35][36] gave a great impulse to the use of timedependent approaches. Exact [37][38][39][40] and approximate [41][42][43][44][45][46][47] time-dependent methods have been applied to van der Waals clusters, most of them triatomic and tetraatomic systems. In a series of papers 5 Zewail and co-workers have reported real-time experiments on the vibrational predissociation ͑VP͒ of the I 2 -Ne n ͑nϭ1-4͒ clusters.…”