Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Electronic and optical properties of Ti_{1-x}Cd_xO2: A first-principles
  prediction   A first-principles study has been carried out to evaluate the electronic and
optical properties of rutile Ti1-xCdxO2 as a possible photocatalytic material.
It was found that Cd incorporation lead to the enhancement of p states in the
top of valence band and the decrease of band gap. The optical transition
between Cd p and O p enhances gradually and shifts to high energy range with
increasing Cd concentration. Furthermore, optical absorption of Ti1-xCdxO2
increases in the visible range.

23
The categories of this paper are: solv-int
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The categories of this paper are: patt-sol
2
The categories of this paper are: math
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
16
The categories of this paper are: stat
7
The categories of this paper are: hep-th
0
The categories of this paper are: hep-ph
26
The categories of this paper are: bayes-an
14
The categories of this paper are: math-ph
33
The categories of this paper are: plasm-ph
5
The categories of this paper are: gr-qc
31
The categories of this paper are: ao-sci
1
The categories of this paper are: cs
21
The categories of this paper are: adap-org