Electronic structure of single layer 1T-NbSe2: interplay of lattice distortions, non-local exchange, and Mott–Hubbard correlations

@article{Kamil2018ElectronicSO,
  title={Electronic structure of single layer 1T-NbSe2: interplay of lattice distortions, non-local exchange, and Mott–Hubbard correlations},
  author={Ebad Kamil and Jan Berges and Gunnar Sch{\"o}nhoff and Malte R{\"o}sner and Malte Sch{\"u}ler and Giorgio Sangiovanni and Tim Oliver Wehling},
  journal={Journal of Physics: Condensed Matter},
  year={2018},
  volume={30}
}
Using ab initio calculations we reveal the nature of the insulating phase recently found experimentally in monolayer 1T-NbSe2. We find soft phonon modes in a large part of the Brillouin zone indicating the strong-coupling nature of a charge-density-wave instability. Structural relaxation of a supercell reveals a Star-of-David reconstruction with an energy gain of 60 meV per primitive unit cell. The band structure of the distorted phase exhibits a half-filled flat band which is associated with… 

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