Quasi-classical trajectory calculations of cross sections and rate constants for the Si + OH → SiO + H reaction

To investigate the dynamics mechanism of the Br + HgBr → Br2 + Hg reaction, the quasi-classical trajectory calculations are performed on Balabanov’s potential energy surface (PES) of ground electronic state. Both the scalar and vector properties are investigated to recognize the dynamics of the title reaction. Reaction probability for the total angular momentum quantum number J = 0 is determined at the collision energies (denoted as Ec) in a range of 1–25 kcal/mol, and the product vibrational distributions are given and compared between Ec = 20 and 40 kcal/mol. Other calculation values characterizing product polarizations including polarization-dependent differential cross sections (PDDCSs), distributions of P(θr), P([Formula: see text]), and P(θr, [Formula: see text]), are all discussed and compared between the two different collision energies in detail to analyze the alignment and orientation characteristics. It is revealed that the products prefer forward scattering and the PDDCSs are anisotropic in the whole range of the scattering angle. The product rotational angular momentum j′ shows a tendency to align perpendicular to the reagent relative velocity k. In fact, the product polarization of the title reaction is weak at both collision energies. In terms of horizontal comparison, the alignment is slightly stronger but the orientation is even less remarkable at higher collision energy.

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COMPARATIVE STUDY OF REACTION RATE CONSTANTS FOR THE NH3 + H → NH2 + H2 REACTION WITH GLOBE DYNAMICS AND TRANSITION STATE THEORIES

Journal of Theoretical and Computational Chemistry ◽

10.1142/s0219633609005325 ◽

2009 ◽

Vol 08 (06) ◽

pp. 1227-1233 ◽

Cited By ~ 1

Author(s):

JU LIPING ◽

LU RUIFENG

Keyword(s):

Transition State ◽

Cross Sections ◽

Rate Constants ◽

Quantum Dynamics ◽

Classical Trajectory ◽

State Theory ◽

Title Reaction ◽

Reaction Rate Constants ◽

Barrier Type ◽

Good Agreement

The nine-dimension quasi-classical trajectory (QCT) calculations have been carried out for the title reaction with a global potential energy surface (PES) constructed by Corchado and Espinosa-García (J Chem Phys106:4013, 1997). The detailed dynamics calculations cover the specific collision energies falling in the range of 0.62–3.04 eV, which are sufficient to fit the calculated reactive cross-sections into a barrier-type excitation function and to obtain the thermal rate constants. The present QCT rate constants are in good agreement with the recent quantum dynamics (QD) results, both of which are much lower than that of the previous variational transition state theory (VTST).

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Correction: Three-Body Collision Based Recombination Rate Constants from Quasi Classical Trajectory Calculations

AIAA Scitech 2021 Forum ◽

10.2514/6.2021-0808.c1 ◽

2021 ◽

Author(s):

Eric C. Geistfeld ◽

Thomas E. Schwartzentruber

Keyword(s):

Rate Constants ◽

Recombination Rate ◽

Classical Trajectory ◽

Trajectory Calculations ◽

Three Body

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Reaction Rate Constants from Classical Trajectories of Atom-Diatomic Molecule Collisions

Zeitschrift für Naturforschung A ◽

10.1515/zna-2008-3-408 ◽

2008 ◽

Vol 63 (3-4) ◽

pp. 159-169

Author(s):

Hamzeh M. Abdel-Halim ◽

Sawsan M. Jaafreh

Keyword(s):

Cross Sections ◽

Rate Constants ◽

Potential Energy Surfaces ◽

Diatomic Molecules ◽

Equations Of Motion ◽

Strong Dependence ◽

Three Dimensional ◽

Reaction Rates ◽

Classical Trajectory ◽

Reaction Rate Constants

Classical trajectory calculations for various atom-diatomic molecules were preformed using the three-dimensional Monte Carlo method. The reaction probabilities, cross-sections and rate constants of several systems were calculated. Equations of motion, which predict the positions and momenta of the colliding particles after each step, have been integrated numerically by the Runge-Kutta-Gill and Adams-Moulton methods. Morse potential energy surfaces were used to describe the interaction between the atom and each atom in the diatomic molecules. The results were compared with experimental ones and with other theoretical values. Good agreement was obtained between calculated rate constants and those obtained experimentally. Also, reasonable agreement was observed with theoretical rate constants obtained by other investigators using different calculation methods. The effects of the temperature, the nature of the colliding particles and the thermochemistry were studied. The results showed a strong dependence of the reaction rates on these factors.

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