Half metal in two-dimensional hexagonal organometallic framework.

Hao Hu,Zhengfei Wang,Feng Liu

doi:10.1186/1556-276x-9-690

Abstract

Two-dimensional (2D) hexagonal organometallic framework (HOMF) made of triphenyl-metal molecules bridged by metal atoms has been recently shown to exhibit exotic electronic properties, such as half-metallic and topological insulating states. Here, using first-principles calculations, we investigate systematically the structural, electronic, and magnetic properties of such HOMFs containing 3d transition metal (TM) series (Sc to Cu). Two types of structures are found for these HOMFs: a buckled structure for those made of TMs with less half-filled 3d band and a twisted structure otherwise. The HOMFs show both ferromagnetic and antiferromagnetic properties, as well as nonmagnetic properties, due to the electronic configuration of the TM atoms. The V, Mn, and Fe lattices are ferromagnetic half metals with a large band gap of more than 1.5 eV in the insulating spin channel, making them potential 2D materials for spintronics application.

Highlights

Half metals, which act as conductor for electrons of one spin orientation, but as insulator for those of opposite spin orientation, have attracted much recent interest [1]
In the present work, using first-principle calculations, we systematically studied the structural, magnetic, and electronic properties of the 2D free-standing hexagonal organometallic framework (HOMF) of triphenyl-transition metal (TM) lattices for all the 3d TMs from Sc to Cu
Our first-principle calculations were based on the spinpolarized density functional theory (DFT) using the generalized gradient approximation (GGA) [23] in the form proposed by Perdew, Burke, and Ernzerhof (PBE) as implemented in the Vienna ab initio simulation package (VASP) code [24]

Summary

Introduction

Half metals, which act as conductor for electrons of one spin orientation, but as insulator for those of opposite spin orientation, have attracted much recent interest [1]. Due to their 100% spin polarization near the Fermi level, the half metals can provide purely spin-resolved electric current, holding great promise for future spintronics and nanoelectronic devices. Most known half metals are ferromagnets, with a few exceptions of half-metallic antiferromagnets [2]; on the other hand, most magnets are not half metals. Much effort has been devoted to searching for new half-metallic materials, including organic half metals and half-metallic nanostructures. Magnetic as well as halfmetallic properties of 2D materials are especially attractive topics of study, because they can be tuned by

Methods

Results

Conclusion