Fabrizio Cossu^1,2,3,4*, Dhani Nafday^4,5, Krisztián Palotás^6,7, Mehdi Biderang⁸, Heung-Sik Kim², Alireza Akbari^4,9,10, Igor Di Marco^4,11,12*

1 School of Physics, Engineering and Technology, University of York, Heslington, York YO10 5DD, England, United Kingdom

2 Department of Physics and Institute of Quantum Convergence and Technology, Kangwon National University, Chuncheon 24341, Korea

3 Department of Physics, School of Natural and Computing Sciences, University of Aberdeen, Aberdeen AB24 3UE, United Kingdom

4 Asia Pacific Center for Theoretical Physics – Pohang, Gyeongbuk 37673, Korea

5 Department of Applied Physics, School of Engineering Sciences, KTH Royal Institute of Technology, AlbaNova University Center, Stockholm SE-10691, Sweden

6 Institute for Solid State Physics and Optics, HUN-REN Wigner Research Center for Physics, H-1525 Budapest, Hungary

7 HUN-REN-SZTE Reaction Kinetics and Surface Chemistry Research Group, University of Szeged, H-6720 Szeged, Hungary

8 Department of Physics, University of Toronto, Toronto, Ontario, M5S 1A7 Canada

9 Beijing Institute of Mathematical Sciences and Applications (BIMSA), Huairou District, Beijing 101408, China

10 Institut für Theoretische Physik III, Ruhr-Universität Bochum, D-44801 Bochum, Germany

11 Institute of Physics, Faculty of Physics, Astronomy and Informatics, Nicolaus Copernicus University, Grudziadzka 5, 87-100 Toruń, Poland

12 Department of Physics and Astronomy, Uppsala University, Box 516, SE-75120 Uppsala, Sweden

* Corresponding authors emails: fabrizio.cossu@york.ac.uk, igor.dimarco@physics.uu.se

DOI10.24435/materialscloud:8a-7h [version v1]

Publication date: Apr 29, 2025

How to cite this record

Fabrizio Cossu, Dhani Nafday, Krisztián Palotás, Mehdi Biderang, Heung-Sik Kim, Alireza Akbari, Igor Di Marco, Stacking of charge-density waves in 2H-NbSe₂ bilayers, Materials Cloud Archive 2025.66 (2025), https://doi.org/10.24435/materialscloud:8a-7h

Description

We employ ab-initio electronic-structure calculations to investigate the charge-density waves and periodic lattice distortions in bilayer 2⁢H-NbSe₂. We demonstrate that the vertical stacking can give rise to a variety of patterns that may lower the symmetry of the charge-density waves exhibited separately by the two composing 1⁢H-NbSe₂ monolayers. The general tendency to a spontaneous symmetry breaking observed in the ground state and the first excited states is shown to originate from a non-negligible interlayer coupling. Simulated images for scanning tunneling microscopy as well as geometric structure factors show signatures of the different stacking orders. This may not only be useful to reinterpret past experiments on surfaces and thin films, but it may also be exploited to devise ad hoc experiments for the investigation of the stacking order in 2H-NbSe₂. We anticipate that our analysis not only applies to the 2H-NbSe₂, but is also relevant for thin films and bulk, whose smallest centrosymmetric component is indeed the bilayer. Finally, our results illustrate clearly that the vertical stacking is not only important for 1T structures, as exemplified by the metal-to-insulator transition observed in 1⁢T-TaS₂, but seems to be a general feature of metallic layered transition metal dichalcogenides as well. The dataset includes the fully relaxed atomic positions of the most favorable charge-density waves, as well as the main output files of the electronic structure calculations. Selected files for the charge densities are also included.

Materials Cloud sections using this data

Files

File name	Size	Description
archive.zip MD5md5:59b4ababe0e2c57d227523eb5a2edd6e	99.2 MiB	DFT data for the most favorable charge-density waves in the 2H-NbSe2 bilayer

License

Files and data are licensed under the terms of the following license: Creative Commons Attribution 4.0 International.
Metadata, except for email addresses, are licensed under the Creative Commons Attribution Share-Alike 4.0 International license.

External references

Keywords

H2020 Marie Curie Fellowship DFT charge density waves stacking order transition metal dichalcogenides