The vanadium Magnéli phases V
نویسنده
چکیده
To compare the metal-insulator transitions (MITs) of VO2 and V2O3 we analyze the relations between the structural and electronic properties of the vanadium Magnéli phases. These materials set up the homologous series VnO2n−1 (3 ≤ n ≤ 9) and have crystal structures comprising typical dioxide-like and sesquioxidelike regions. As the MITs of the vanadium Magnéli phases are accompanied by structural transformations, we are able to discuss the effects of characteristic changes in the local atomic environments. The systematic investigation of the transport properties is based on a new and unifying description of the crystal structures of the Magnéli phases including VO2 and V2O3. Our results lead to a comprehensive understanding of the MITs in the Magnéli class and shed new light on the role of particular electronic states for the MIT of V2O3.
منابع مشابه
Switching adhesion forces by crossing the metal–insulator transition in Magnéli-type vanadium oxide crystals
Magnéli-type vanadium oxides form the homologous series V(n)O(2) (n) (-1) and exhibit a temperature-induced, reversible metal-insulator first order phase transition (MIT). We studied the change of the adhesion force across the transition temperature between the cleavage planes of various vanadium oxide Magnéli phases (n = 3 … 7) and spherical titanium atomic force microscope (AFM) tips by syste...
متن کاملA pr 2 00 4 Charge order , orbital order , and electron localization in the Magnéli phase
The metal-insulator transition of the Magnéli phase Ti 4 O 7 is studied by means of augmented spherical wave (ASW) electronic structure calculations as based on density functional theory and the local density approximation. The results show that the metal-insulator transition arises from a complex interplay of charge order, orbital order, and singlet formation of those Ti 3d states which mediat...
متن کاملCharge storage in oxygen deficient phases of TiO2: defect Physics without defects
Defects in semiconductors can exhibit multiple charge states, which can be used for charge storage applications. Here we consider such charge storage in a series of oxygen deficient phases of TiO2, known as Magnéli phases. These Magnéli phases (TinO2n-1) present well-defined crystalline structures, i.e., their deviation from stoichiometry is accommodated by changes in space group as opposed to ...
متن کاملCoulomb-potential-dependent decohesion of Magnéli phases.
Transition metal oxide Magnéli phases are traditionally described as crystallographic shear structures. Some of these phases feature a layered crystal structure based on deformed metal-oxygen octahedra. Here, we describe the correlation between structure, decohesion energies and elastic properties of WO(3), ReO(3), MoO(2), VO(2), V(2)O(5) and TiO(2) using ab initio calculations. Decohesion ener...
متن کاملTrace Amounts Determination of Vanadium (V) Using a New Kinetic-Catalytic Reaction System
This study describes a new simple, sensitive and selective catalytic kinetic spectrophotometricmethod for the determination of vanadium (V). The method is based upon the catalytic effect ofvanadium (V) on the oxidation of Carminic acid by bromate in sulfuric acid media. The reaction wasfollowed spectrophotometrically by measuring the decrease in absorbance at 490 nm and thedependence of sensiti...
متن کامل