Dislocations and grain boundaries in two-dimensional boron nitride.

@article{Liu2012DislocationsAG,
  title={Dislocations and grain boundaries in two-dimensional boron nitride.},
  author={Yuanyue Liu and Xiaolong Zou and Boris I. Yakobson},
  journal={ACS nano},
  year={2012},
  volume={6 8},
  pages={
          7053-8
        }
}
A new dislocation structure-square-octagon pair (4|8) is discovered in two-dimensional boron nitride (h-BN), via first-principles calculations. It has lower energy than corresponding pentagon-heptagon pairs (5|7), which contain unfavorable homoelemental bonds. On the basis of the structures of dislocations, grain boundaries (GB) in BN are investigated. Depending on the tilt angle of grains, GB can be either polar (B-rich or N-rich), constituted by 5|7s, or unpolar, composed of 4|8s. The polar… 

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