Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Probing frontier orbital energies of (Co9(P2W15)3) polyoxometalate
  clusters at molecule-metal and molecule-water interfaces   Functionalization of polyoxotungstates with organoarsonate co-ligands
enabling surface decoration was explored for the triangular cluster
architectures of the composition
[CoII9(H2O)6(OH)3(p-RC6H4AsVO3)2({\alpha}-PV2WVI15O56)3]25-({Co9(P2W15)3}, R =
H or NH2), isolated as Na25[Co9(OH)3(H2O)6(C6H5AsO3)2(P2W15O56)3]86H2O (Na-1)
and Na25[Co9(OH)3(H2O)6(H2NC6H4AsO3)2(P2W15O56)3]86H2O (Na-2). The axially
oriented para-aminophenyl groups in 2 facilitate the formation of
self-assembled monolayers on gold surfaces, and thus provide a viable molecular
platform for charge transport studies of magnetically functionalized
polyoxometalates. The title systems were isolated and characterized in the
solid state and in aqueous solutions, and on metal surfaces. Using conducting
tip atomic force microscopy (C-AFM), the energies of {Co9(P2W15)3} frontier
molecular orbitals in the surface-bound state were found to directly correlate
with cyclic voltammetry data in aqueous solution.

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The categories of this paper are: nlin
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The categories of this paper are: supr-con
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The categories of this paper are: chem-ph
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The categories of this paper are: mtrl-th
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The categories of this paper are: q-fin
2
The categories of this paper are: math
10
The categories of this paper are: q-bio
12
The categories of this paper are: nucl-th
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The categories of this paper are: hep-th
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The categories of this paper are: chao-dyn
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The categories of this paper are: nucl-ex
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The categories of this paper are: gr-qc
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The categories of this paper are: eess
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The categories of this paper are: astro-ph
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The categories of this paper are: plasm-ph
0
The categories of this paper are: hep-ph