Isotope effect of the stereodynamics for the reactions F + HO → HF + O and F + DO → DF + O

Abstract

Based on the 13A″ triplet state the product polarizations for the reactions F + HO → HF + O and F + DO → DF + O are studied by using the quasi-classical trajectory (QCT) method. The four generalized polarization-dependent differential cross-sections (PDDCSs) (2π/σ)(dσ00/dωt), (2π/σ)(dσ20/dωt), (2π/σ)(dσ22+/dωt) and (2π/σ)(dσ21−/dωt) have been calculated in the centre-of-mass frame. The distribution of the angle between k and j′, P(θr), the distribution of the dihedral angle denoting k − k′ − j′ correlation, P(ϕr), as well as the angular distribution of product rotational vectors in the form of polar plots P(θr,ϕr) are calculated. The evident influence of isotope substitution on the product polarization is revealed. This effect may be derived from the different mass factor or the effective potential well depth in the two reactions.

Isotope effect of the stereodynamics in the reactions F+HCl→HF+Cl and F+DCl→DF+Cl

“…It is seen from Figure 2(a) that the products are backward-scattered in F+HCl and F+DCl reactions, more so for the DF products (θ t =180°). The behavior of (2π/σ)(dσ 00 /dω t ) for the title reactions differs from that of the other HLH reaction system F+HO/F+DO, where the HF product molecules from the reaction F+HO are forwardscattered, while the DF molecules from the reaction F+DO are backward-scattered [36]. The PDDCS (2π/σ)(dσ 20 /dω t ), which is the expectation value of the second Legendre moment 2 (cos ) r P θ , is drawn in Figure 2(b).…”

Quasi-classical trajectory approach to the stereo-dynamics of the reaction F + HO → HF + O

“…[14,[16][17][18][19][20][21][22][23][24][26][27][28][29][30]. The classical Hamilton's equations are numerically integrated in three dimensions.…”

“…The general theory of the product rotational polarization is standard [16][17][18][19][20][21][22][23][24][26][27][28][29][30][31][32][33][34][35][36][37][38][39], and here we only summarize the details relevant to the present work. In the center-of-mass (CM) frame shown in Figure 1, the reagent relative velocity vector k is parallel to the z axis and the xz plane is the scattering plane containing the initial and final relative ve- Figure 1 The center-of-mass coordinate system used to describe the k, k′ and j′ distribution.…”

“…For this reason, we studied the influences of collision energy and rotational excitation of reagents on product polarization for the reaction H + FO  OH + F, and the results indicate that both the orientation and the alignment of the rotational angular moment were impacted by collision energies [20,21]. In addition, we have studied the isotope effect of the stereo-dynamics for the reactions F + H(D)O  H(D)F + O, and the evident influence of isotope substitution on the product polarization was revealed [22]. Recently, we have also investigated the axial polarization of product molecules for reaction H + FO  HF + O [23] and the effect of the reagent vibration on stereodynamics of the reaction O( 1 D)+HF O( 1 D) + HF  F + OH [24].…”

Vector correlations in the F + HO → HF + O reaction and its isotopic variant

“…Gómez-Carrasco et al also investigated the potential surfaces for this OHF reactive system, and they successfully constructed a series of PESs (potential energy surfaces) for the different electronic states of the system [4][5][6]. Based on these PESs and employed the one for the 3 A" electronic state, Gonzalez-Sanchez et al [7], Zhao et al [8,9], and Han et al [10] reported the stereodynamics characters of the OHF system. With another 3 A' state, we investigated the stereodynamics of the two product channels in the H + FO reaction [11].…”