Time-dependent quantum wave packet study of the Ar+H2+→ArH++H reaction on a new ab initio potential energy surface for the ground electronic state (12A′)

Abstract

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Wave packet and statistical quantum calculations for the He + NeH+ → HeH+ + Ne reaction on the ground electronic state

“…In Figure 3, the similarities between QM-CC and QM-CS reaction probabilities for low J values (J = 10) are quite clear but differences increase with the increase of total angular mo-mentum. These findings are in accordance with the results for other atom-molecular ion systems 4,8,11 for which it has been observed that Coriolis coupling becomes more important as the value of J increases. The contributions of each K state to the total QM-CC reaction probabilities for v 0 = 0, j 0 = 0, 1, and J = 10, 40 are presented in Figure 5.…”

“…Theoretical studies require, then, larger spatial grid sizes, making the quantum dynamical simulation computationally expensive. [1][2][3][4][5][6][7][8][9][10][11][12][13] Many of these systems possess no activation barrier in the entrance channel. As a result, a large number of partial waves is required to converge the cross sections and the J-shifting method usually does not work very well.…”

“…It is then not surprising that the structure and dynamics of, for example, RgH + 2 (Rg = He, Ne, Ar) systems, have been the subject of a large number of both theoretical and experimental studies: ab initio electronic structure, ro-vibrational spectra, reaction cross sections, and rate constants have been calculated before. 4,[6][7][8][15][16][17][18][19][20][21][22][23][24][25][26] Complexes containing two rare gas atoms and a proton are also well studied. 12,[27][28][29][30][31][32][33][34][35][36] Both RgH + 2 a) t.gonzalez.lezana@csic.es b) adi07@iitg.ernet.in and [RgHRg/Rg ] + cases are found to display a global potential energy minimum at the collinear configuration.…”

“…12 show remarkable differences between the CS and CC approaches, in accordance with the results obtained for other ion-molecule systems. 7,8,[10][11][12] Recently, we have explored the electronic structural details of [RgHRg ] + (Rg = He, Ne, Ar) 35 type of systems.…”

Quantum astrochemical spectroscopy

“…These computations also show that it takes roughly 0.5 eV of energy to climb out of the ArH 1 2 minimum and produce ArH 1 and H. This may likely be a natural pathway for the energetics since ArH 1 2 may be too transient in this reaction to be observed. [113] Interestingly, NeH 1 2 is also the minimum on its potential surface, but the first step out of this well is to neutral Ne and H 2 not NeH 1 and a hydrogen atom. As such, it is unlikely that NeH 1 will form in a similar pathway as its argon analogue casting doubt on its interstellar observability.…”