Bonding, Backbonding, and Spin-Polarized Molecular Orbitals: Basis for Magnetism and Semiconducting Transport in V[TCNE]x~2
نویسندگان
چکیده
X-ray absorption spectroscopy (XAS) and magnetic circular dichroism (MCD) at the V L2,3 and C and N K edges reveal bonding/backbonding interactions in films of the 400 K magnetic semiconductor V[TCNE]x~2. In V spectra, dxy-like orbitals are modeled assuming V in an octahedral ligand field, while dz2 and dx2-y2 orbitals involved in strong covalent bonding cannot be modeled by atomic calculations. C and N MCD, and differences in XAS from neutral TCNE molecules, reveal spin-polarized molecular orbitals in V[TCNE]x~2 associated with backbonding interactions that yield its novel properties. PACS: 75.50.Xx, 61.05.cj, 33.55.+b, 78.20.Ls
منابع مشابه
Magnetism in single metalloorganic complexes formed by atom manipulation.
The magnetic properties of molecular structures can be tailored by chemical synthesis or bottom-up assembly at the atomic scale. We used scanning tunneling microscopy to study charge and spin transfer in individual complexes of transition metals with the charge acceptor, tetracyanoethylene (TCNE). The complexes were formed on a thin insulator, Cu2N on Cu(100), by manipulation of individual atom...
متن کاملSpin-polarized transport through a zigzag-edge graphene flake embedded between two armchair nanoribbons electrodes
We study the coherent spin-polarized transport through a zigzag-edge graphene flake (ZGF), using Hubbard model in the nearest neighbor approximation within the framework of the Green function’s technique and Landauer formalism. The system considered consists of electrode/ (ZGF)/electrode, in which the electrodes are chosen to be armchair nanoribbons. The study was performed for two types of ele...
متن کاملTuning molecule-mediated spin coupling in bottom-up-fabricated vanadium-tetracyanoethylene nanostructures.
We have fabricated hybrid magnetic complexes from V atoms and tetracyanoethylene ligands via atomic manipulation with a cryogenic scanning tunneling microscope. Using tunneling spectroscopy we observe spin-polarized molecular orbitals as well as Kondo behavior. For complexes having two V atoms, the Kondo behavior can be quenched for different molecular arrangements, even as the spin-polarized o...
متن کاملElectrical spin injection from an organic-based ferrimagnet in a hybrid organic-inorganic heterostructure.
We report the successful extraction of spin-polarized current from the organic-based room temperature ferrimagnetic semiconductor V[TCNE](x) (x∼2, TCNE: tetracyanoethylene; T(C)∼400 K, E(G)∼0.5 eV, σ(300 K)∼10(-2) S/cm) and its subsequent injection into a GaAs/AlGaAs light-emitting diode. The spin current tracks the magnetization of V[TCNE](x∼2), is weakly temperature dependent, and exhibit...
متن کاملVacancy Defects Induced Magnetism in Armchair Graphdiyne Nanoribbon
Spin-polarized electronic and transport properties of Armchair GraphdiyneNanoribbons (A-GDYNR) with single vacancy (SV), two types of configurations fordouble vacancy (DV1, DV2) and multi vacancy (MV) defects are studied by nonequilibriumGreen’s function (NEGF) combined with density functional theory (DFT).The results demonstrate that the A-GDYNR with the SV has the lowe...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
دوره شماره
صفحات -
تاریخ انتشار 2008