Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Factors Responsible for the Stability and the Existence of a Clean
  Energy Gap of a Silicon Nanocluster   We present a critical theoretical study of electronic properties of silicon
nanoclusters, in particular the roles played by symmetry, relaxation, and
hydrogen passivation on the the stability, the gap states and the energy gap of
the system using the order-N [O(N)] non-orthogonal tight-binding molecular
dynamics and the local analysis of electronic structure.

37
The categories of this paper are: supr-con
2
The categories of this paper are: math
5
The categories of this paper are: gr-qc
30
The categories of this paper are: q-alg
23
The categories of this paper are: solv-int
9
The categories of this paper are: nlin
18
The categories of this paper are: econ
33
The categories of this paper are: plasm-ph
27
The categories of this paper are: comp-gas
15
The categories of this paper are: nucl-ex
28
The categories of this paper are: alg-geom
11
The categories of this paper are: hep-lat
22
The categories of this paper are: chao-dyn
3
The categories of this paper are: physics
31
The categories of this paper are: ao-sci
24
The categories of this paper are: dg-ga