Coupling and Anisotropy of 3d Transition-Metal Nanowire on the Surface of Graphyne Sheet'
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Introduction
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Since the synthesis of two-dimensional (2D) graphene[@1; @2], much research has been focused on it due to its unique properties and tremendous possible applications in nanoscale devices.[@3; @4; @5] Graphyne (GY), a 2D carbon allotrope with the same symmetry as graphene predicted to have a high possibility of synthesis[@6; @7], is made up of hexagonal carbon rings and acetylene linkages. Graphdiyne(GDY), belonging to the family of GY has been successfully grown on the surface of copper recently.[@8; @9] Consequently, the preparation of GY can be expected because theoretical work has shown that it is energetically more stable than GDY. Previous work has shown that the surface adsorption of TM atom profoundly influences the electronic properties of graphene and induces spin polarization[@10; @11; @12; @13; @14; @15] in the system, which makes it a vital candidate for spintronics[@16; @17; @18]. Likewise, in our previous work[@19], the adsorption of single 3d TM atom on GY sheet will promote magnetization of the TM-GY system, which indicates that the TM-GY systems are potential candidates for spintronics. Moreover, recent studies based on DFT+U approach[@18], auxiliary-field quantum Monte Carlo[@23], and 