Organometallic Wires Constructed from Transitional Metals and Anthracene: A Theoretical Study Xianlong Wang, Xiaohong Zheng and Zhi Zeng ∗ (Dated: September 14, 2018) The properties of organometallic wires [TM 2 (Ant)] ∞ constructed with transitional metals (TM = Sc, Ti, V, Cr, Mn and Fe) and anthracene (Ant) are investigated by first-principles calculations. As the gap between HOMO (Highest Occupied Molecular Orbital) and LUMO (Lowest Unoccu- pied Molecular Orbital) of Ant is much smaller than that of benzene (Bz), much larger charge transfer (CT) occurs between TMs and Ant, which results in much more diverse magnetic prop- erties in [TM 2 (Ant)] ∞ than in [TM(Bz)] ∞ . Particularly, [V 2 (Ant)] ∞ and [Cr 2 (Ant)] ∞ are found to be half-metallic ferromagnets. As a result of this and the better structural stability, compared with [TM(Bz)] ∞ , [TM 2 (Ant)] ∞ (like [V 2 (Ant)] ∞ and [Cr 2 (Ant)] ∞ ) may be better candidates of spintronic devices. Furthermore, as the HOMO-LUMO gap of small pieces of graphene (SPG), such as pentacene and coronene, decreases with the increase of polycyclic number, the CT effects may also fit for the TM-SPG sandwich polymers which can also act as good spintronic materials. Abstract ∗ Correspondence author: zzeng@theory.issp.ac.cn 1 arXiv:1002.4327v1 [cond-mat.mtrl-sci] 23 Feb 2010 Key Laboratory of Materials Physics, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei 230031, P.R. China