Li L Y, Lin L, Han L H, First-principles study on electronic structure and magnetic properties of （V，Mn） co-doped SnSe₂ [J].Journal of Henan Polytechnic University(Natural Science) ,2026,45(6):193-199.

doi:10.16186/j.cnki.1673-9787.2024070052

Received:2024/07/11

Revised:2024/09/26

Published:2026/10/09

First-principles study on electronic structure and magnetic properties of （V，Mn） co-doped SnSe₂

Li Lingyun1, Lin Long2, Han Linhao2

1.Do-Fluoride New Materials Co.， Ltd.， Jiaozuo  454150， Henan， China；2.School of Materials Science and Engineering， Henan Polytechnic University， Jiaozuo  454003， Henan， China

Abstract: Objectives To systematically explore the extraordinary properties arising from the unique "chalcogen-metal-chalcogen" layered architecture of transition metal dichalcogenides， this work focuses on the modification of two-dimensional SnSe2， a representative transition metal dichalcogenide. By delving into interatomic interactions， this study aims to provide novel insights for the design and development of advanced functional materials.  Methods First-principles calculations based on density functional theory （DFT） are adopted. The exchange-correlation functional within the generalized gradient approximation （GGA）， coupled with the Hubbard U correction （GGA+U）， is applied to account for the strong electron correlation effect of transition metal 3d orbitals， ensuring the calculation accuracy of electronic structures and magnetic properties. A 4×4×1 supercell of SnSe₂ monolayer is constructed as the computational substrate， and four calculation models are established respectively： pristine SnSe₂， transition metal （V， Mn） mono-doped SnSe₂， and V-Mn co-doped SnSe₂. After full geometric relaxation of all models to achieve convergence of total energy and atomic forces， key physical quantities including band structure， partial density of states， atomic magnetic moment distribution， spin polarization characteristics and optical absorption coefficient are systematically computed， and the differences in physical properties and underlying microscopic mechanisms under different doping modes are comparatively analyzed.  Results Firstly，it is calculated that intrinsic SnSe₂ is a direct bandgap semiconductor material with a band gap of 0.781 eV and that intrinsic SnSe₂ is not magnetic. Next，it is calculated that V，Mn singly doped SnSe₂ has magnetic moments due to the introduction of V，Mn atoms that spin-polarize the electrons of the V 3d，Mn 3d，and Se 4p states in the vicinity of the Fermi energy level，resulting in a net magnetic moment that reveals ferromagnetism. Subsequent calculations of the electronic and magnetic properties of the V，Mn co-doped SnSe₂ system show that the source of magnetism is mainly through the transition metal V，Mn 3d orbital electrons inducing spin polarization of the surrounding Se 4p state electrons presenting ferromagnetism. Conclusions Modulation of the magnetic and optical properties of SnSe₂ by doping makes SnSe₂ a potential two-dimensional material for spintronic and optoelectronic devices.

Key words: SnSe; electronic structure; magnetism; optical property; first principle