J. Matsuno

Different routes to charge disproportionation in perovskite-type Fe oxides

Iron perovskites CaFeO 3 and La 0 . 3 3 Sr 0 . 6 7 FeO 3 show charge disproportionation, resulting in charge-ordered states with Fe 3 + :Fe 5 + = 1:1 and =2:1, respectively. We have made photoemission and unrestricted Hartree-Fock band-structure calculations of CaFeO 3 and compared it with La 0 . 3 3 Sr 0 . 6 7 (FeO 3 . With decreasing temperature, a gradual decrease of the spectral weight near the Fermi level occurred in CaFeO 3 as in La 0 . 3 3 Sr 0 . 6 7 FeO 3 although lattice distortion occurs only in CaFeO 3 . Hartree-Fock calculations have indicated that both the breathing and tilting distortions are necessary to induce the charge disproportionation in CaFeO 3 , while no lattice distortion is necessary for the charge disproportionation in La 0 . 3 3 Sr 0 . 6 7 FeO 3 .

Core-level photoemission measurements of the chemical potential shift as a probe of correlated electron systems

Abstract The shift of the chemical potential as a function of band filling provides useful insight into the electronic structure of solids. In this article, we describe how the chemical potential shift can be measured using core-level photoemission spectroscopy and what information can be obtained from the measured chemical potential shift, in particular on strongly correlated systems. We present results on various transition-metal oxides, which include materials showing typical Fermi-liquid behavior, pseudogap behavior, charge–density wave formation, ‘stripe’ formation, etc.

Chemical potential shift in La1 − xSrxMnO3: Photoemission test of the phase separation scenario

We have studied the chemical potential shift in La1 − xSrxMnO3 as a function of doped hole concentration by core-level X-ray photoemission. The shift is monotonous, which means that there is no electronic phase separation on a macroscopic scale, whereas it is consistent with the nanometer scale cluster formation induced by chemical disorder. Comparison of the observed shift with the shift deduced from the electronic specific heat indicates that hole doping in La1 − xSrxMnO3 is well described by the rigid-band picture. In particular no mass enhancement toward the metal-insulator boundary was implied by the chemical potential shift, consistent with the electronic specific-heat data.

Electronic structure of spinel-type LiV 2 O 4

The band structure of the cubic spinel compound

Chemical potential shift in Nd 2 − x Ce x CuO 4 : Contrasting behavior between the electron- and hole-doped cuprates

{\mathrm{LiV}}_{2}{\mathrm{O}}_{4}

Soft X-ray magnetic circular dichroism study of the ferromagnetic spinel-type Cr chalcogenides

, which has been reported recently to show heavy Fermion behavior, has been calculated within the local-density approximation using a full-potential version of the linear augmented-plane-wave method. The results show that partially filled V

Effects of Charge Disproportionation on the Phonon Density of States in Fe Perovskites

3d

Doping dependence of the electronic structure of Ba 1 − x K x BiO 3 studied by x-ray-absorption spectroscopy

bands are located about 1.9 eV above the O

Chemical Potential Shift in Nd

2p

_{2-x}

bands and the V