Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Thermally stimulated H emission and diffusion in hydrogenated amorphous
  silicon   We report first principles ab initio density functional calculations of
hydrogen dynam- ics in hydrogenated amorphous silicon. Thermal motion of the
host Si atoms drives H diffusion, as we demonstrate by direct simulation and
explain with simple models. Si-Si bond centers and Si ring centers are local
energy minima as expected. We also describe a new mechanism for break- ing Si-H
bonds to release free atomic H into the network: a fluctuation bond center
detachment (FBCD) assisted diffusion. H dynamics in a-Si:H is dominated by
structural fluctuations intrinsic to the amorphous phase not present in the
crystal.

31
The categories of this paper are: ao-sci
21
The categories of this paper are: adap-org
34
The categories of this paper are: chem-ph
19
The categories of this paper are: eess
1
The categories of this paper are: cs
20
The categories of this paper are: acc-phys
27
The categories of this paper are: comp-gas
35
The categories of this paper are: mtrl-th
2
The categories of this paper are: math
16
The categories of this paper are: stat
17
The categories of this paper are: q-fin
37
The categories of this paper are: supr-con
32
The categories of this paper are: atom-ph
26
The categories of this paper are: bayes-an
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The categories of this paper are: alg-geom
10
The categories of this paper are: q-bio