One-Dimensional Transition Metal-Benzene Sandwich Polymers: Possible Ideal Conductors for Spin Transport

摘要

We investigate the electronic and magnetic properties of the proposedone-dimensional transition metal (TM=Sc, Ti, V, Cr, and Mn)-benzene (Bz)sandwich polymers by means of density functional calculations.[V(Bz)]$_{\infty}$ is found to be a quasi-half-metallic ferromagnet andhalf-metallic ferromagnetism is predicted for [Mn(Bz)]$_{\infty}$. Moreover, weshow that stretching the [TM(Bz)]$_{\infty}$ polymers could have dramaticeffects on their electronic and magnetic properties. The elongated[V(Bz)]$_{\infty}$ displays half-metallic behavior, and [Mn(Bz)]$_{\infty}$stretched to a certain degree becomes an antiferromagnetic insulator. Thepossibilities to stabilize the ferromagnetic order in [V(Bz)]$_{\infty}$ and[Mn(Bz)]$_{\infty}$ polymers at finite temperature are discussed. We suggestthat the hexagonal bundles composed by these polymers might display intrachainferromagnetic order at finite temperature by introducing interchain exchangecoupling.