Structure And Magnetic Properties Of Two Dimensional Cluster-assembled Materials Based On TM@Si₁₂?TM=3d Transition Metal?

As a typical representative of the quantum size effect,atom clusters exhibit rich and interesting physicochemical properties and great potential application.The cluster-based assembly materials?CAM?show excellent controllability,because their properties can be manipulated by adjusting the structure,size,and composition of its structural unit clusters.It has become a very significant research field in the design of nanomaterials by assembling certain cluster building units and adopting a“bottom-up”approach to assemble the material with the desired function.In this paper,the geometric structures,stabilities,electronic properties and magnetic properties of four kinds assembled two-dimensional?2D?lattice materials,with hexagonal prism-like TM@Si₁₂(transition metal-doped Si₁₂)clusters as building blocks,were systematically investigated by the first-principles density functional theory?DFT?and molecular dynamics simulation?MD?.The results show that the four different types of 2D self-assembled lattices have higher stability than the corresponding unit TM@Si₁₂2 clusters,and the hexagonal honeycomb and porous structure are more stable than the other two lattices.The first-principles molecular dynamics studies have shown that these two hexagonal lattices can maintain their thermodynamic stability even at room temperature.Therefore,the magnetic coupling properties of these 3d-TM@Si₁₂2 clusters self-assembled honeycomb and porous were further studied in detail.The results show that almost all of the hexagonal lattices exhibit a certain degree of magnetic ordering properties.These studies provide a new insight into the effective design of 2D spintronic materials.Finally,we further explored the stress control and diffusion studies of Li atom adsorption of two stable hexagonal structures to seek a new application of the 2D assembly materials.