Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Structure and stability of copper clusters : A tight-binding molecular
  dynamics study   In this paper we propose a tight-binding molecular dynamics with parameters
fitted to first-principles calculations on the smaller clusters and with an
environment correction, to be a powerful technique for studying large
transition/noble metal clusters. In particular, the structure and stability of
$Cu_n$ clusters for $n=3-55$ are studied by using this technique. The results
for small $Cu_n$ clusters ($n=3-9$) show good agreement with {\it ab initio}
calculations and available experimental results. In the size range $10\le n \le
55$ most of the clusters adopt icosahedral structure which can be derived from
the 13-atom icosahedron, the polyicosahedral 19-, 23-, and 26-atom clusters and
the 55-atom icosahedron, by adding or removing atoms. However, a local
geometrical change from icosahedral to decahedral structure is observed for $n
= 40-44$ and return to the icosahedral growth pattern is found at $n=45$ which
continues. Electronic "magic numbers" ($n=2$, 8, 20, 34, 40) in this regime are
correctly reproduced. Due to electron pairing in HOMOs, even-odd alternation is
found. A sudden loss of even-odd alternation in second difference of cluster
binding energy, HOMO-LUMO gap energy and ionization potential is observed in
the region $n\sim40$ due to structural change there. Interplay between
electronic and geometrical structure is found.

34
The categories of this paper are: chem-ph
27
The categories of this paper are: comp-gas
11
The categories of this paper are: hep-lat
35
The categories of this paper are: mtrl-th
14
The categories of this paper are: math-ph
8
The categories of this paper are: hep-ex
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
29
The categories of this paper are: funct-an
19
The categories of this paper are: eess
20
The categories of this paper are: acc-phys
5
The categories of this paper are: gr-qc
26
The categories of this paper are: bayes-an
4
The categories of this paper are: cond-mat
31
The categories of this paper are: ao-sci