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Localized to itinerant electronic transition

Localized to Itinerant Electronic Transition in Perovskite Oxides... [Pg.243]

Goodenough, J.B. and Zhou, J.S. Localized to itinerant electronic transitions in transition-metal oxides with the perovskite structure. Chem. Mater. 1998, 10, 2980-2993. [Pg.193]

The transition from localized to itinerant electronic behavior occurs where the interatomic interactions become greater than the intraatomic interactions. A measure of the strength of the interatomic interactions is the bandwidth W and of the strength of the intraatomic interactions is the energy C/eff that separates successive redox energies. The transition from localized to itinerant electronic behavior occurs where... [Pg.260]

Our canvas here is to provide a qualitative description of current models for the NM-M transition, developed for both metal-ammonia and metal-methylamine solutions. For this purpose we also draw upon interpretations from other systems in which the transition from localized to itinerant electron regimes is well recognized (78). [Pg.169]

Of particular interest for the present volume are perovskite-related oxides in which M is a 3d-block transition-metal atom and the A sites are occupied by a lanthanide, yttrium, and/or an alkaline earth. Alkali ions can also be accommodated in the larger A sites, which are coordinated by twelve oxygen near neighbors. With a transition-metal atom M, the thermal expansion of the (A—0) bond is greater than that of the (M—O) bond, so t increases with temperature. Normally the (A—O) bond is also more compressible than the (M—0) bond, which makes t decrease with increasing pressure [4]. However, at a transition from localized to itinerant electronic behavior, an unusually high compressibility of the (M—O) bond results in a dt/dP > 0 (see Eq. (20) below) [5]. [Pg.3]

The ability to adjust to a t < 1 allows for extensive cation substitutions on both the A and M sites the structure is also tolerant of large concentrations of both oxygen and cation vacancies. The perovskites considered in this volume are stoichiometric with MO3 arrays containing a single transition-metal atom M. Emphasis is given to the peculiar physical properties that occur at the transition from localized to itinerant electronic behavior and from Curie-Weiss to Pauli paramagnetism at a Mott-Hubbard transition on the MO3 array. The transition from localized to itinerant electronic behavior can be approached from either the itinerant-electron side or the localized-electron side in single-valent MO3 arrays by isovalent substitutions on the A sites that vary the tolerance factor t. It can also be crossed in mixed-valent... [Pg.3]

A reduced covalent mixing at V(III) relative to V(IV) makes W,j < U in the LnVOa perovskites. However, the t configuration at the V(III) ions of LaV03 appears to be near the transition from localized to itinerant electronic behavior ... [Pg.27]

A transition from localized to itinerant electronic behavior occurs with increasing x in the VO3 array whereas in the TiOs array there is only a crossing of the Mott-Hubbard transition from strongly to weakly correlated electrons. [Pg.57]


See other pages where Localized to itinerant electronic transition is mentioned: [Pg.491]    [Pg.491]    [Pg.491]    [Pg.491]    [Pg.253]    [Pg.261]    [Pg.282]    [Pg.285]    [Pg.304]    [Pg.306]    [Pg.311]    [Pg.315]    [Pg.332]    [Pg.332]    [Pg.604]    [Pg.260]    [Pg.278]    [Pg.1]    [Pg.4]    [Pg.59]    [Pg.66]    [Pg.72]    [Pg.89]    [Pg.92]    [Pg.248]    [Pg.248]    [Pg.253]    [Pg.261]    [Pg.282]    [Pg.285]    [Pg.304]    [Pg.306]    [Pg.311]    [Pg.315]    [Pg.332]    [Pg.44]    [Pg.283]    [Pg.344]   
See also in sourсe #XX -- [ Pg.282 ]

See also in sourсe #XX -- [ Pg.282 ]




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Electron localization

Itinerant

Itinerant electrons

Localization transition

Localizing electrons

Transition from localized to itinerant electronic

Transition from localized to itinerant electronic behavior

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