STM micrograph of a polycrystalline VS2 sample. The pattern represents the modulation of the electron density distribution caused by the arrangement of sulfur atoms. In addition to the cell structure the existence of a superstructure - charge density waves (CDW) - is visualized by parallel rows of elevations of different heights.

Magonov, S., Cantow, H.J., Hillebrecht, H., Drechsler, M., Rotter, W. (1989)
The atomic structure and superstructure of vanadium disulfide by scanning tunneling microscopy.
Eur.J.Cell Biol. 83,60.