Quantum Scattering Calculations on Chemical Reactions

Articles you may be interested inThe importance of accurate adiabatic interaction potentials for the correct description of electronically nonadiabatic vibrational energy transfer: A combined experimental and theoretical study of NO(v = 3) collisions with a Au (111) In this work we seek to examine the nature of collisional energy transfer between HCl and Au(111) for nonreactive scattering events that sample geometries near the transition state for dissociative adsorption by varying both the vibrational and translational energy of the incident HCl molecules in the range near the dissociation barrier. Specifically, we report absolute vibrational excitation probabilities for HCl(v = 0 → 1) and HCl(v = 1 → 2) scattering from clean Au(111) as a function of surface temperature and incidence translational energy. The HCl(v = 2 → 3) channel could not be observed-presumably due to the onset of dissociation. The excitation probabilities can be decomposed into adiabatic and nonadiabatic contributions. We find that both contributions strongly increase with incidence vibrational state by a factor of 24 and 9, respectively. This suggests that V-T as well as V-EHP coupling can be enhanced near the transition state for dissociative adsorption at a metal surface. We also show that previously reported HCl(v = 0 → 1) excitation probabilities [Q. Ran et al., Phys. Rev. Lett. 98, 237601 (2007)]-50 times smaller than those reported here-were influenced by erroneous assignment of spectroscopic lines used in the data analysis. Published by AIP Publishing. [http://dx

Section: Introductionmentioning

confidence: 99%

Vibrational energy transfer near a dissociative adsorption transition state: State-to-state study of HCl collisions at Au(111)

Geweke

Shirhatti

Rahinov

et al. 2016

“…2 The TID-CC method has particular advantages for treating systems requiring relative small numbers of basis functions and/or collisions with very low kinetic energy. It can now be routinely applied to study light triatomic systems, such as H + H 2 , F+H 2 , and Cl+ H 2 reactions and their isotopically substituted analogs, 3,4 and has provided valuable insights into chemical reaction dynamics.…”

Section: Introductionmentioning

confidence: 99%

Extraction of state-to-state reactive scattering attributes from wave packet in reactant Jacobi coordinates

Sun

Guo

Zhang

2010

138

126

The S-matrix for a scattering system provides the most detailed information about the dynamics. In this work, we discuss the calculation of S-matrix elements for the A + BC→ AB+ C, AC+ B type reaction. Two methods for extracting S-matrix elements from a single wave packet in reactant Jacobi coordinates are reviewed and compared. Both methods are capable of extracting the state-to-state attributes for both product channels from a single wave packet propagation. It is shown through the examples of H + HD, Cl+ H 2 , and H + HCl reactions that such reactant coordinate based methods are easy to implement, numerically efficient, and accurate. Additional efficiency can be gained by the use of a L-shaped grid with two-dimensional fast Fourier transform.

“…Aoiz et al recently reviewed the progress in the study of the dynamics of this reaction. 26 With advances in experimental 27,28 and theoretical 29 methods very good agreement between theory and experiment has been achieved and only a few issues remain unresolved. 26 Several global analytic potential energy surfaces ͑PESs͒ are available, the LSTH surface, 30,31 the DMBE surface, 32 and the BKMP ͑Ref.…”

Section: Introductionmentioning

confidence: 99%

State-to-state reactive differential cross sections for the H+H2→H2+H reaction on five different potential energy surfaces employing a new quantum wavepacket computer code: DIFFREALWAVE

Hankel

Smith²,

Allan³

et al. 2006

Reaction cross sections for the H+D 2 (ν 0 =1)→HD+D and D+H 2 (ν 0 =1)→DH+H systems. A multiconfiguration time-dependent Hartree (MCTDH) wave packet propagation study J. Chem. Phys. 116, 10641 (2002) State-to-state differential cross sections have been calculated for the hydrogen exchange reaction, H+H 2 → H 2 + H, using five different high quality potential energy surfaces with the objective of examining the sensitivity of these detailed cross sections to the underlying potential energy surfaces. The calculations were performed using a new parallel computer code, DIFFREALWAVE. The code is based on the real wavepacket approach of Gray and Balint-Kurti ͓J. Chem. Phys. 108, 950 ͑1998͔͒. The calculations are parallelized over the helicity quantum number ⍀Ј ͑i.e., the quantum number for the body-fixed z component of the total angular momentum͒ and wavepackets for each J , ⍀Ј set are assigned to different processors, similar in spirit to the Coriolis-coupled processors approach of Goldfield and Gray ͓Comput. Phys. Commun. 84, 1 ͑1996͔͒. Calculations for J =0-24 have been performed to obtain converged state-to-state differential cross sections in the energy range from 0.4 to 1.2 eV. The calculations employ five different potential energy surfaces, the BKMP2 surface and a hierarchical family of four new ab initio surfaces ͓S. L. Mielke, et al., J. Chem. Phys. 116, 4142 ͑2002͔͒. This family of four surfaces has been calculated using three different hierarchical sets of basis functions and also an extrapolation to the complete basis set limit, the so called CCI surface. The CCI surface is the most accurate surface for the H 3 system reported to date. Our calculations of differential cross sections are the first to be reported for the A2, A3, A4, and CCI surfaces. They show that there are some small differences in the cross sections obtained from the five different surfaces, particularly at higher energies. The calculations also show that the BKMP2 performs well and gives cross sections in very good agreement with the results from the CCI surface, displaying only small divergences at higher energies.