Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: First-principles study of bandgap effects in graphene due to hydrogen
  adsorption   Hydrogen adsorption on graphene in commensurate periodic arrangements leads
to bandgap opening at the Dirac point and the emergence of dispersionless
midgap bands. We study these bandgap effects and their dependence on
periodicity for a single hydrogen adsorbate on periodic graphene supercells
using spin-polarized density-functional theory calculations. Our results show
that for certain periodicities, marked by a scale factor of three, the bandgap
is suppressed to a great extent, and has a special level structure around the
neutrality point. We present explanations for the origin of the changes to the
band structure in terms of the \textit{ab initio} Hamiltonian matrix. This
method may be used to obtain a more accurate tight-binding description of
single hydrogen adsorption on graphene.

37
The categories of this paper are: supr-con
22
The categories of this paper are: chao-dyn
5
The categories of this paper are: gr-qc
11
The categories of this paper are: hep-lat
32
The categories of this paper are: atom-ph
30
The categories of this paper are: q-alg
26
The categories of this paper are: bayes-an
20
The categories of this paper are: acc-phys
12
The categories of this paper are: nucl-th
24
The categories of this paper are: dg-ga
10
The categories of this paper are: q-bio
35
The categories of this paper are: mtrl-th
14
The categories of this paper are: math-ph
34
The categories of this paper are: chem-ph
3
The categories of this paper are: physics
33
The categories of this paper are: plasm-ph