Quantum dynamical calculations for the vibrational predissociation of the He–ICl complex: Product rotational distribution

Stabilization and rovibronic spectra of the T -shaped and linear ground-state conformers of a weakly bound raregas-homonuclear dihalogen complex: He Br 2He 79 Br 2 B,v=8←X,v ″ =0 excitation spectrum: Ab initio prediction and spectroscopic manifestation of a linear isomer Spectroscopic features attributed to rovibronic transitions from both the T-shaped and linear He¯I 35 Cl(X) and He¯I 37 Cl(X) ground-state complexes have been recorded in the ICl B 3 ⌸ 0ϩ -X 1 ⌺ ϩ , 2-0 and 3-0 spectral regions using laser-induced fluorescence spectroscopy. Experiments performed using varying expansion conditions indicate that the He¯I 35,37 Cl(X) complex with a linear equilibrium orientation lies lower in energy than the separately localized T-shaped isomer even though the transition energies of the T-shaped and linear complexes are shifted by ϳ3.5 and ϳ14 cm Ϫ1 to higher energy than the I 35,37 Cl B -X band origins, respectively. Based on comparison with the excited state theoretical predictions of Waterland et al. ͓J. Chem. Phys. 92, 4261 ͑1990͔͒, estimates of the binding energies for the ground state T-shaped and linear He¯I 35 Cl(X) complexes are 17 and 21 cm Ϫ1 , respectively, in qualitative agreement with the recently published predictions of 15.2 and 18.3 cm Ϫ1 obtained using high level ab initio theory for the ground state potential energy surface ͓J. Chem. Phys. 117, 7017 ͑2002͔͒.

Section: High-resolution Spectramentioning

confidence: 99%

Spectroscopic observation of the preferentially stabilized, linear He⋯ICl(X 1Σ+) complex

Bradke

Loomis

2003

“…Many experiments have been carried out for different rare gases ͑He,Ne,Ar͒ bound to molecules such as I 2 , 1-3 Cl 2 , 4-6 and ICl, [7][8][9] and a broad variety of behavior has been found, ranging from vibrational to translational ͑V-T͒ energy transfer ͓as in HeI 2 ͑Ref. 10͔͒ to intramolecular vibrational redistribution ͑IVR͒ ͓as in ArCl 2 ͑Ref.…”

Section: Introductionmentioning

confidence: 99%

Vibrational predissociation dynamics of the He79Br2 van der Waals molecule: A quantum mechanical study

González‐Lezana

Hernández

Delgado‐Barrio

et al. 1996

Articles you may be interested in A full-dimensional quantum approach to the vibrational predissociation of tetra-atomic complexes based on the partially-separable time-dependent self-consistent-field approximation Oneatom cage effect in collinear I2(B)-Ar complexes: A timedependent wave packet study Validity of a hybrid quantum/classical approach in photodissociation/recombination of I2 in rare gas matrices A three-dimensional time-dependent self-consistent-field TDSCF approach is proposed to study the vibrational predissociation of the I 2 (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 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.

“…19,28,29 , HeICl 30 and NeBr 2 14,31 in which many classical predictions were later confirmed by EQM 32 . More recently, some of us have explored the extent to which the Gaussian weighted (GW) trajectory method 33,34 adds to the applicability of QCT in the study of RgBr 2 (Rg = He, Ne, Ar) molecules 35 .…”

Section: Introductionmentioning

confidence: 74%

Quasi-classical trajectories study of Ne2Br2(B) vibrational predissociation: Kinetics and product distributions

Arbelo-González

González-Martínez

Reed

et al. 2012

The vibrational predissociation of the Ne 2 Br 2 (B ) van der Waals complex has been investigated using the quasi-classical trajectory method (QCT), in the range of vibrational levels v ′ = 16-23. Extensive comparison is made with the most recent experimental observations [Pio et al., J. Chem. Phys. 133, 014305 (2010)], molecular dynamics with quantum transitions (MDQT) simulations [Miguel et al., Faraday Discuss. 118, 257 (2001)], and preliminary results from 24-dimensional Cartesian coupled coherent state (CCCS) calculations. A sequential mechanism is found to accurately describe the theoretical dynamical evolution of intermediate and final product populations, and both QCT and CCCS provide very good estimates for the dissociation lifetimes. The capabilities of QCT in the description of the fragmentation kinetics is analyzed in detail by using reduced-dimensionality models of the complexes and concepts from phase-space transport theory. The problem of fast decoupling of the different coherent states in CCCS simulations, resulting from the high dimensionality of phase space, is tackled using a re-expansion scheme. QCT ro-vibrational product state distributions are reported. Due to the weakness of the vdW couplings and the low density of vibrational states, QCT predicts a larger than observed propensity for ∆v ′ = −1 and −2 channels for the respective dissociation of the first and second Ne atoms.