Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Can optical spectroscopy directly elucidate the ground state of C20?   The optical response of the lowest energy members of the C20 family is
calculated using time-dependent density functional theory within a real-space,
real-time scheme. Significant differences are found among the spectra of the
different isomers, and thus we propose optical spectroscopy as a tool for
experimental investigation of the structure of these important clusters.

37
The categories of this paper are: supr-con
24
The categories of this paper are: dg-ga
16
The categories of this paper are: stat
26
The categories of this paper are: bayes-an
23
The categories of this paper are: solv-int
9
The categories of this paper are: nlin
5
The categories of this paper are: gr-qc
11
The categories of this paper are: hep-lat
12
The categories of this paper are: nucl-th
21
The categories of this paper are: adap-org
28
The categories of this paper are: alg-geom
2
The categories of this paper are: math
27
The categories of this paper are: comp-gas
0
The categories of this paper are: hep-ph
1
The categories of this paper are: cs
33
The categories of this paper are: plasm-ph