Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Wigner-Witmer diatomic eigenfunction   Born and Oppenheimer reported an approximate separation of molecular
eigenfunctions into electronic, vibrational, and rotational parts, but at the
end of their paper showed that the two angles describing rotation of the nuclei
in a diatomic molecule are exactly separable. A year later in a two-part work
devoted strictly to diatomic molecules, Wigner and Witmer published (1) an
exact diatomic eigenfunction and (2) the rules correlating the electronic state
of a diatomic molecule to the orbital and spin momenta of the separated atoms.
The second part of the Wigner-Witmer paper became famous for its correlation
rules, but, oddly, the exact eigenfunction from which their rules were obtained
received hardly any attention. Using three fundamental symmetries, we give a
derivation of the Wigner-Witmer diatomic eigenfunction. Applications of our
derivations are fundamental to predicting accurate diatomic molecular spectra
that we compare with recorded spectra for diagnostic purposes, such as
measurements of molecular spectra following generation of laser-induced plasma.

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The categories of this paper are: astro-ph
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The categories of this paper are: atom-ph
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The categories of this paper are: funct-an
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The categories of this paper are: stat
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The categories of this paper are: nlin
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The categories of this paper are: math
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The categories of this paper are: cmp-lg
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The categories of this paper are: dg-ga
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The categories of this paper are: adap-org
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The categories of this paper are: hep-ex
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The categories of this paper are: nucl-th
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The categories of this paper are: cs
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The categories of this paper are: mtrl-th
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The categories of this paper are: gr-qc
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The categories of this paper are: comp-gas
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The categories of this paper are: quant-ph