Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Vibrational analysis of methyl cation - rare gas atom complexes:
  CH$_3^+$-Rg (Rg=He, Ne, Ar, Kr)   The vibrational spectra of simple CH$_3^+$-Rg (Rg=He, Ne, Ar, Kr) complexes
have been studied by vibrational configuration interaction (VCI) theory relying
on multidimensional potential energy surfaces (PES) obtained from explicitly
correlated coupled cluster calculations, CCSD(T)-F12a. In agreement with
experimental results, the series of rare gas atoms leads to rather unsystematic
results and indicates huge zero point vibrational energy effects for the helium
complex. In order to study these sensitive complexes more consistently, we also
introduce configuration averaged vibrational self-consistent field theory
(CAVSCF), which is a generalization of standard VSCF theory to several
configurations. The vibrational spectra of the complexes are compared to that
of the methyl cation, for which corrections due to scalar-relativistic effects,
high-level coupled-cluster terms, i.e. CCSDTQ, and core-valence correlation
have explicitly been accounted for. The occurrence of tunneling splittings for
the vibrational ground-state of CH$_3^+$-He has been investigated on the basis
of semiclassical instanton theory. These calculations and a direct comparison
of the energy profiles along the intrinsic reaction coordinates (IRC) with that
of the hydronium cation, H$_3$O$^+$, suggest that tunneling effects for
vibrationally excited states should be very small.

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The categories of this paper are: adap-org
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The categories of this paper are: chao-dyn
12
The categories of this paper are: nucl-th
37
The categories of this paper are: supr-con
25
The categories of this paper are: patt-sol
8
The categories of this paper are: hep-ex
35
The categories of this paper are: mtrl-th
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The categories of this paper are: solv-int
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The categories of this paper are: dg-ga
1
The categories of this paper are: cs
10
The categories of this paper are: q-bio
9
The categories of this paper are: nlin
11
The categories of this paper are: hep-lat
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The categories of this paper are: funct-an
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The categories of this paper are: comp-gas
20
The categories of this paper are: acc-phys