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相关论文: Synthesis and structure of new pyrochlore-type oxi…

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We have succeeded in synthesizing single-phase polycrystalline samples of oxygen-deficient oxypnictide superconductors, LnFeAsO1-y (Ln: lanthanide elements) with Ln=La, Ce, Pr, Nd, Sm, Gd, Tb and Dy using high-pressure synthesis technique.…

In this article we report the structural stability of Er$_2$Ti$_2$O$_7$ cubic pyrochlore with pressure using x-ray diffraction, Raman spectroscopy, photoluminescence, x-ray absorption and ab-initio calculations. Our studies establish a…

材料科学 · 物理学 2024-06-07 M. Modak , Rahul Kaiwart , Santosh K. Gupta , A. Dwivedi , K. K. Pandey , A. K. Poswal , H. K. Poswal

The cubic symmetry of pyrochlore iridium oxides R2Ir2O7 (R = Nd, Eu, and Pr) has been investigated by high resolution X-ray diffraction experiments down to 4 K,in order to clarify the relationship between the metal-insulator transition…

强关联电子 · 物理学 2014-12-12 Hiroshi Takatsu , Kunihiko Watanabe , Kazuki Goto , Hiroaki Kadowaki

Neutron powder diffraction and inelastic measurements were performed examining the 5d pyrochlore Y$_2$Ir$_2$O$_7$. Temperature dependent measurements were performed between 3.4 K and 290 K, spanning the magnetic transition at 155 K. No sign…

强关联电子 · 物理学 2014-05-30 M. C. Shapiro , S. C. Riggs , M. B. Stone , C. R. de la Cruz , S. Chi , A. A. Podlesnyak , I. R. Fisher

We applied synchrotron single-crystal X-ray diffraction in a diamond anvil cell at 48-51 GPa and first-principles theoretical calculations to study the crystal structure of solid atomic iodine at high pressure. We report the synthesis of…

We address the concomitant metal-insulator transition (MIT) and antiferromagnetic ordering in the novel pyrochlore iridate Eu2Ir2O7 by combining x-ray absorption spectroscopy, x-ray and neutron diffractions and density functional theory…

The two published lithium peroxide structures, both ascribed to the hexagonal P -6 space group, were subjected to reinterpretation and another more symmetric structure, now belonging to the P 63/m m c space group, was found. Detailed…

原子与分子团簇 · 物理学 2007-05-23 Luis Guillermo Cota , Pablo de la Mora

Large single crystals of the pyrochlore Pr2Hf2O7 have been successfully grown by the floating zone technique using an optical furnace equipped with high power Xenon arc lamps. Structural investigations have been carried out by both…

Our searches for new oxide chalcogenides of rare earths and Fe, Co, Ni, and Zn resulted in preparation of two new compounds Ce2Fe2O3S2 and Pr2Fe2O3S2 which are isostructural to La2Fe2O3Se2 and Sm2Ti2O3Sb2. Crystal structures of the new…

材料科学 · 物理学 2011-10-20 D. O. Charkin , V. A. Plotnikov , A. V. Sadakov , O. E. Omel'yanovskii , S. M. Kazakov

Rare-earth pyrochlores are known to exhibit exotic magnetic phenomena. We report a study of crystal growth and characterizations of a new rare-earth compound Er$_2$AlSbO$_7$, in which Al$^{3+}$ and Sb$^{5+}$ ions share the same positions…

We have synthesized a new layered oxychalcogenide La2O2Bi3AgS6. From synchrotron X-ray diffraction and Rietveld refinement, the crystal structure of La2O2Bi3AgS6 was refined using a model of the P4/nmm space group with a = 4.0644(1) {\AA}…

The 5d-transition metal pyrochlore oxide Cd2Re2O7, which was recently suggested to be a prototype of the spin-orbit-coupled metal [Phys. Rev. Lett. 115, 026401 (2015)], exhibits an inversion-symmetry breaking (ISB) transition at 200 K and a…

Understanding the response of ceramics operating in extreme environments is of interest for a variety of applications. Ab initio molecular dynamic simulations have been used to investigate the effect of structure and $B$-site (=Ti, Zr)…

材料科学 · 物理学 2019-06-04 Michel Sassi , Tiffany Kaspar , Kevin M. Rosso , Steven R. Spurgeon

Polycrystalline samples of F-substituted LnOBiS2 (Ln = La, Ce, Pr, Nd, Yb) compounds were synthesized by solid-state reaction. The samples were characterized by x-ray diffraction measurements and found to have the ZrCuSiAs crystal…

超导电性 · 物理学 2013-01-18 D. Yazici , K. Huang , B. D. White , A. H. Chang , A. J. Friedman , M. B. Maple

We study the pyrochlore series (Eu$_{1-x}$Bi$_x$)$_2$Ir$_2$O$_7$ for $ 0 \leq x \leq 1$. We show that for small $x$, the lattice undergoes an anomalous contraction but the all-in/all-out and metal-to-insulator transitions remain robust, and…

强关联电子 · 物理学 2019-06-05 Prachi Telang , Kshiti Mishra , Giacomo Prando , A. K. Sood , Surjeet Singh

Pyrochlore erbium titanate samples in the form of powders (with nominal compositions of Er2Ti2+xO7) and bulk single crystals were prepared to elucidate the effect of synthesis and growth conditions on their composition, structure, and…

材料科学 · 物理学 2018-12-14 Q. Wang , A. Ghasemi , A. Scheie , S. M. Koohpayeh

The pyrochlore oxide Pb2Re2O7-{\delta} (PRO) is a candidate spin-orbit-coupled metal (SOCM) that exhibits a structural phase transition with inversion symmetry breaking. In this study, we report the results of detailed X-ray diffraction…

A2Ir2O7 iridates were proven to crystallise in the geometrically frustrated pyrochlore structure, which remains stable upon rare-earth cation substitution, temperature variation, and external pressure application. However, the change of…

强关联电子 · 物理学 2024-08-05 Daniel Staško , Petr Proschek , Jiří Prchal , Milan Klicpera

Low-temperature powder neutron diffraction measurements are performed in the ordered magnetic state of the pyrochlore antiferromagnet Gd2Sn2O7. Symmetry analysis of the diffraction data indicates that this compound has the ground state…

The orthorhombic crystal structure of the novel molecular-inorganic polymer $\mathrm{K_{2}SeO_{4}\cdot H_{2}SeO_{3}}$ was elucidated using single-crystal X-ray diffraction with MoK$\alpha$ radiation ($\lambda$= 0.71073 {\AA}), performed at…