相关论文: Local Structure and Spin Transition in Fe2O3 Hemat…
We report the first high pressure measurement of the Fe K-edge in hematite (Fe$_2$O$_3$) by X-ray absorption spectroscopy in partial fluorescence yield geometry. The pressure-induced evolution of the electronic structure as Fe$_2$O$_3$…
First principles density functional calculations for Fe$_{2}$O$_{3}$ has been performed over a wide range of pressures. The ground state is corundum-type hematite and is an antiferromagnetic insulator. This is in good agreement with…
Iron sesquioxide (Fe2O3) displays pressure and temperature induced spin and structural transitions. Our calculations show that, density functional theory (DFT), in the generalized gradient approximation (GGA) scheme, is capable of capturing…
Structural, magnetic and electrical-transport properties of {\alpha}-LiFeO2, crystallizing in the rock salt structure with random distribution of Li and Fe ions, have been studied by synchrotron X-ray diffraction, 57Fe M\"ossbauer…
Structural changes in REMnO3 (RE= Y, Ho, Lu) under high pressure were examined by synchrotron x-ray diffraction methods at room temperature. Compression occurs more readily in the ab plane than along the c-axis. Under hydrostatic pressure…
The discovery of FeO$_{2}$ containing more oxygen than hematite (Fe$_{2}$O$_{3}$) that was previously believed to be the most oxygen rich iron compounds, has important implications on the study of the deep lower mantle compositions.…
The Local Density Approximation combined with Dynamical Mean-Field Theory (LDA+DMFT method) is applied to the study of the paramagnetic and magnetically ordered phases of hematite Fe$_2$O$_3$ as a function of volume. As the volume is…
High pressure can provoke spin transitions in transition metal-bearing compounds. These transitions are of high interest not only for fundamental physics and chemistry, but also may have important implications for geochemistry and…
The local electronic and magnetic properties of superconducting FeSe have been investigated by K$\beta$ x-ray emission (XES) and simultaneous x-ray absorption spectroscopy (XAS) at the Fe K-edge at high pressure and low temperature. Our…
We investigate the pressure-induced evolution of crystal structure and magnetism in the kagome ferromagnet Fe$_3$Sn$_2$ by combining X-ray diffraction, X-ray Emission Spectroscopy, X-ray Magnetic Circular Dichroism, and spin-polarized…
Electrochemical oxidation of hematite ({\alpha}-Fe2O3) nano-particulate films at 600 mV vs. Ag+/AgCl reference in KOH electrolyte forms a species at the hematite surface which causes a new transition in the upper Hubbard band between the…
We provide experimental and theoretical evidence for a novel type of pressure-induced insulator-metal transition characterized by site-selective delocalization of the electrons. M\"ossbauer spectroscopy, X-ray diffraction and electrical…
High-pressure x-ray absorption spectroscopy was performed at the Ir $L_3$ and $L_2$ absorption edges of Sr$_3$Ir$_2$O$_7$. The branching ratio of white line intensities continuously decreases with pressure, reflecting a reduction in the…
The spin order in cubic perovskite SrFeO3 and BaFeO3 under high pressure is studied by density functional theory (DFT) calculation with local spin density approximation plus Hubbard U (LSDA+U). At ambient pressure, A-type and G-type helical…
We employ a combination of the \emph{ab initio} band structure methods and dynamical mean-field theory to determine the electronic structure and phase stability of paramagnetic FeO at high pressure and temperature. Our results reveal a…
We present in-situ x-ray diffraction and velocity measurements of Fe$_2$O$_3$ under laser shock compression at pressures between 38-116 GPa. None of the phases reported by static compression studies were observed. Instead, we observed an…
Local structural measurements have been performed on hexagonal HoMnO3 in order to ascertain the specific changes in bond distances which accompany magnetic ordering transitions. The transition from paramagnetic to the antiferromagetic…
We study the structural evolution of Sr$_3$Ir$_2$O$_7$ as a function of pressure using x-ray diffraction. At a pressure of 54 GPa at room temperature, we observe a first-order structural phase transition, associated with a change from…
Using spin-density functional theory we investigated various possible structures of the hematite (0001) surface. Depending on the ambient oxygen partial pressure, two geometries are found to be particularly stable under thermal equilibrium:…
The archetypal $3d$ Mott insulator hematite, Fe$_2$O$_3$, is one of the basic oxide components playing an important role in mineralogy of Earth's lower mantle. Its high pressure-temperature behavior, such as the electronic properties,…