Combined SnS@SnS₂ double layers: charge transfer and electronic structure

The present paper focuses on the interactions between single SnS and SnS₂ monolayers and the properties of the combined SnS@SnS₂ double-layer system. These materials occur as structural elements in inorganic nanotubes. We have employed density-functional theory-based methods to calculate structural, energetic, and electronic properties of these structures. Thereby, we have put emphasis on the difference between the two single layers and the double-layer system with special consideration of an occurring charge transfer from SnS₂ to SnS. We will show that the interlayer interplay is beyond a simple non-bonding van-der-Waals interaction, which contrasts the properties of many other layered structures and makes combined SnS@SnS₂ a unique material. (paper)