State‐Resolved Stereodynamics of an Insertion Reaction O(¹D₂) + H₂(v = 0, j) → OH(X²Π_i; v′, N′, f′) + H

Abstract

The product state-resolved stereodynamics of the reaction of O('D,) with H, have been studied at 300 K at a mean collision energy of ca. 12 kJ mol-I, using polarized, Doppler-resolved laser-induced fluorescence to probe the scattered products, OH(X211i; v' = 0, N', f), and polarized photodissociation of N,O to provide the reagent O('D,) atoms. Product state-resolved differential cross sections, rotational polarizations, and excitation functions are in very good qualitative agreement with the results of quasi-classical trajectory (QCT) calculations, conducted on the Schinke-Lester, SLl ab initio potential energy surface (PES) for the ground electronic state of the collision complex. The experimental and computational results are compared with those obtained in a complementary study of the reaction of O(lD,) with CH, and remarkable parallels have been exposed. The linear and angular momentum vector correlations are all consistent with an "insertion" mechanism, proceeding over an attractive PES, which presents no entrance barrier.

Dynamical studies and product analysis of O(1D) + H2/D2reactions

“…When they are considered, Branda˜o and Rio [45] obtained rate constants in close agreement with experiment, [46]. (---) QCT results using the K PES [51]. (i) QCT results using the DK PES [16].…”

“…The agreement is good and validates the use of classical mechanics in these studies. Also in this figure we show the QCT results using the K PES [51] and the trajectory results on the DK PES [16].…”

Quantum mechanical and quasi-classical trajectory reaction probabilities and cross sections for the S(1D) + H2,D2,HD insertion reactions

“…We retain between 1600 and 7500 functions, depending on r (from 1.8 to 15.1 a 0 ). For total angular momentum J ¼ 0, the scattering wave function is expanded on a basis of 289 states for H 2 S [286 states for SD 2 ] dissociating at large hyperradius into the H 2 (16,14,10,8,0) and SH (44,41,38,34,31,26,21,15,1) [D 2 (18,14,10,6) and SD (50,46,42,37,32,26,17)] rovibrational sets (this notation indicates the largest rotational level j for each vibrational manifold v ¼ 0-4 for H 2 and v 0 ¼ 0-8 for SH [v ¼ 0-3 for D 2 and v 0 ¼ 0-6 for SD]). The coefficients of the expansion satisfy a set of secondorder coupled differential equations with couplings arising from the difference between the exact hamiltonian and the reference hamiltonian.…”

Quantum mechanical calculation of product state distributions for the O(1D)+H2→OH+H reaction on the ground electronic state surface

“…There have been a large number of experimental studies of thermal rate coefficients, 2,3 product vibrational [4][5][6] and rotational [7][8][9] distributions, integral cross sections, 10 and angular and translational distributions. [11][12][13][14][15][16][17][18] Theoretical studies include both classical trajectory [19][20][21][22][23][24][25] as well as quantum mechanical calculations. [26][27][28][29][30][31][32] The interaction of electronically excited oxygen with hydrogen molecules…”