Full-Dimensional Theory of Pair-Correlated HNCO Photofragmentation

Abstract

Full-dimensional semiclassical dynamical calculations combining classical paths and Bohr quantization of product internal motions are reported for the prototype photofragmentation of isocyanic acid in the S state. These calculations allow one to closely reproduce for the first time key features of state-of-the-art imaging measurements at photolysis wavelengths of 201 and 210 nm while providing insight into the underlying dissociation mechanism. Quantum scattering calculations being beyond reach for most polyatomic fissions, pair-correlated data on these processes are much more often measured than predicted. Our theoretical approach can be used to fill this gap.

When Classical Trajectories Get to Quantum Accuracy: The Scattering of H2on Pd(111)

“…[1][2][3][4][5][6][7][8][9][10] For chemical reactions involving a small number of degrees-of-freedom (DOF) (typically less than or equal to 6), quantum dynamics calculations might be now regarded as exact since they generally provide results in excellent agreement with experiments. 11,12 However, reaction dynamics studies focus on systems of ever increasing size [13][14][15][16][17][18][19][20][21][22][23][24][25][26][27][28] for which the quasi-classical trajectory (QCT) method is at this time the only practical tool to apply. A crucial issue is thus to develop theoretically justified corrections to carry out classical dynamics studies of chemical reactions in a quantum spirit.…”

Imaging Isocyanic Acid Photodissociation at 193 nm: the NH(a1Δ)+CO(X1Σ+) Channel

“…Moreover, Bonnet et al provided new insight into the dissociation mechanism. The observed bimodal rotational distribution of CO should be the consequence of an impulsive-deflective mechanism due to two repulsive walls of the 6D PES, the first one producing rotationally hot CO products and the second one cooling part of them [34].…”

“…It implies that both low-j and high-j components are from HNCO rapid dissociation via a repulsive surface on S 1 . Recently, by fulldimensional theoretical calculation, Bonnet et al [34] reproduced the bimodal rotational state distribution of CO. Our experimental results are further verified by theoretical calculation. Moreover, Bonnet et al provided new insight into the dissociation mechanism.…”

State-to-state dissociative photoionization of molecular nitrogen: the full story

“…For instance, the present findings may help to fully understand the isotopic effects observed recently in the ultrafast dynamics of dissociative photoionization of N 2 and the unexpected branching ratios measured recently during the dissociation dynamics of N 2 + induced by isolated attosecond XUV pulses in combination with few-optical-cycle near-infrared/visible (NIR/VIS) [30]. Similar approaches can be applied also to explain the isotopic effects in the VUV photodissociation of the N 2 and CO molecules [16,82] and that of larger molecular systems relevant for astrophysical, planetary, and atmospheric media and having environmental impacts such as HNCO [83].…”