Layer-dependent properties of SnSe2 two-dimensional materials

Bo-Yu Chen¹, Po-Han Lee^1*

¹Affiliated Senior High School, National Taiwan Normal University, Taipei, Taiwan

* Presenter:Po-Han Lee, email:leepohan@gmail.com

The first-principles density functional theory (DFT) is used to investigate the layer dependent structural, electronic and vibrational properties of SnSe2. In the SnSe2 nanosheet, the Sn atoms are placed in-between the Se atoms in the fascinations of Se–Sn–Se layer. The full-potential linearized augmented plane wave (FLAPW) implemented by the Wien2k package to identify the Density of states (DOS), and the exchange-correlation terms are calculated by using PBESOL of generalized gradient approximation (GGA). Additionally, the k-points grid is set as 16×16×7 in bulk calculations, 25×25×3 in mono-layer calculations, and 27×27×2 in two-layer calculations, and RKM is all set as (RMT×Kmax)=7. By using the ab initio method to calculate the DOS of SnSe2, the calculated magnetic state is obtained by no-magnetic states (NM). The DOS results of mon- and two-layer SnSe2 illustrate that the gap of 0.49 eV, 1.61 eV, 0.57 eV in bulk, mon- and two-layer of SnSe2. The property of energy gap is maintained in these three types of SnSe2 and the largest one occurs in the monolayer-SnSe2.

Keywords: DFT, 2D material, SnSe2