Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Quantum dynamics of the intramolecular vibrational energy redistribution
  in OCS: From localization to quasi-thermalization   We report a fully quantum-dynamical study of the intramolecular vibrational
energy redistribution (IVR) in the electronic ground state of carbonyl sulfide
(OCS), which is a prototype of an isolated many-body quantum system with strong
internal couplings and non-Rice-Ramsperger-Kassel-Marcus (RRKM) behavior. We
pay particular attention to the role of many-body localization and the approach
to thermalization, which currently are topics of considerable interest, as they
pertain to the very foundations of statistical mechanics and thermodynamics. We
employ local-mode (valence) coordinates and consider initial excitations
localized in one local mode, with energies ranging from low to near the
dissociation threshold, where the classical dynamics have been shown to be
chaotic. We propagate the nuclear wavepacket on the potential energy surface by
means of the numerically exact multiconfiguration time-dependent Hartree method
and employ mean local energies, time-dependent and time-averaged populations in
quantum number space, energy distributions, entanglement entropies, local
population distributions, microcanonical averages, and dissociation
probabilities, as diagnostic tools. This allows us to identify a continuous
localization $\rightarrow$ delocalization transition in the energy flow,
associated with the onset of quantum chaos, as the excitation energy increases
up to near the dissociation threshold. Moreover, we find that at this energy
and $\sim$1 ps the molecule nearly thermalizes. Furthermore, we observe that
IVR is so slow that the molecule begins to dissociate well before such
quasi-thermalization is complete, in accordance with earlier
classical-mechanical predictions of non-RRKM behavior.

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The categories of this paper are: cond-mat
35
The categories of this paper are: mtrl-th
22
The categories of this paper are: chao-dyn
21
The categories of this paper are: adap-org
1
The categories of this paper are: cs
29
The categories of this paper are: funct-an
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The categories of this paper are: hep-th
37
The categories of this paper are: supr-con
18
The categories of this paper are: econ
30
The categories of this paper are: q-alg
32
The categories of this paper are: atom-ph
28
The categories of this paper are: alg-geom
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The categories of this paper are: nlin
20
The categories of this paper are: acc-phys
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The categories of this paper are: hep-lat
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The categories of this paper are: q-bio