A5087106352- Advanced Condensed Matter Physics
- Magnetic and transport properties of perovskites and related materials
- Multiferroics and related materials
- Nuclear materials and radiation effects
- Pigment Synthesis and Properties
- Physics of Superconductivity and Magnetism
- Ferroelectric and Piezoelectric Materials
- Crystal Structures and Properties
- Microwave Dielectric Ceramics Synthesis
- Advanced Thermoelectric Materials and Devices
- X-ray Diffraction in Crystallography
- Luminescence Properties of Advanced Materials
- Transition Metal Oxide Nanomaterials
- Crystallization and Solubility Studies
- Chemical Synthesis and Characterization
- Cultural Heritage Materials Analysis
- Electronic and Structural Properties of Oxides
- Dielectric properties of ceramics
- Rare-earth and actinide compounds
- Thermal Expansion and Ionic Conductivity
- Iron-based superconductors research
- Advanced Photocatalysis Techniques
- Inorganic Chemistry and Materials
- Inorganic Fluorides and Related Compounds
- Radioactive element chemistry and processing
Oregon State University
2016-2025
Madurai Medical College
2018
Corvallis Environmental Center
2017
Annamalai University
2016
Florida State University
2009-2015
Wilmington University
1998-2009
DuPont (United States)
1998-2009
Experimental Station
1997-2009
University of California, Santa Barbara
2009
Institut de Chimie de la Matière Condensée de Bordeaux
2005-2006
A new superconductor that displays onset behavior near 120 K has been identified as Bi 2 Sr 3- x Ca Cu O 8+ y with ranging from about 0.4 to 0.9. Single crystal x-ray diffraction data were used determine a pseudo-tetragonal structure based on an A-centered orthorhombic subcell = 5.399 Å, b 5.414 and c 30.904 Å. The contains copper-oxygen sheets in La CuO 4 YBa 3 7 , but the chains present do not occur . is made up of alternating double bismuth-oxygen sheets. There are 2+ cations between...
Neutron diffraction studies confirm that La2NiMnO6 is ferromagnetic with moments on Ni and Mn indicating NiII MnIV (small large spheres, respectively, in Figure). Electrical resistivity measurements show semiconducting behavior a room temperature conductivity of ∼102 Ω cm very high at low temperature. On application magnetic field, significant changes electrical dielectric constant occur temperatures as 280 K. Supporting information for this article available the WWW under...
Isostructural ZrW2O8 and HfW2O8 show strong negative thermal expansion from 0.3 K up to their decomposition temperatures of approximately 1050 K. This behavior is especially unusual because these compounds are apparently cubic over entire existence range. Detailed structural studies were conducted using high-resolution neutron powder diffraction data taken at 14 693 Below 428 K, adopts the acentric space group P213 has a well-ordered structure containing corner-sharing ZrO6 octahedra two...
The discovery of high-temperature superconductivity in doped copper oxides, which their insulating forms are nearly ideal two-dimensional spin-1/2 Heisenberg antiferromagnets, has stimulated great interest finding additional examples such magnetic systems. We find that ${\mathrm{Sr}}_{2}$${\mathrm{IrO}}_{4}$, the ${\mathrm{K}}_{2}$${\mathrm{NiF}}_{4}$ structure and should have a 5${\mathit{d}}^{5}$ low-spin (S=1/2) electronic configuration, develops ferromagnetic moment near 250 K. small...
Abstract The sluggish ion diffusion and electrolyte freezing with volumetric changes limit the low‐temperature performance of rechargeable batteries. Herein, a high‐rate aqueous proton battery (APB) operated at below −78 °C via 62 wt% (9.5 m) H 3 PO 4 is reported. APB rocking‐chair that operates protons commuting between Prussian blue cathode an MoO anode. At °C, full cells exhibit stable cycle life for 450 cycles, high round‐trip efficiency 85%, appreciable power performance. delivers 30%...
We report the observation of large low-field magnetoresistance (MR) behavior in ${\mathrm{CaCu}}_{3}{\mathrm{Mn}}_{4}{\mathrm{O}}_{12}$ with a perovskite-related $({\mathrm{AA}}^{\ensuremath{'}}_{3}B_{4}{\mathrm{O}}_{12})$ structure. ${\mathrm{Ca}}^{2+}{\mathrm{Cu}}_{3}^{2+}{\mathrm{Mn}}_{4}^{4+}{\mathrm{O}}_{12}$ is semiconducting and orders ferromagnetically at 355 K. However, it has neither mixed valency Mn for double-exchange magnetic interactions, nor Jahn-Teller ${\mathrm{Mn}}^{3+}$...
Structural, electrical, and thermal transport properties of CoSb3 partially filled with indium are reported. Polycrystalline samples InxCo4Sb12 (0 ≤ x 0.3) were prepared by solid-state reaction under a gas mixture 5% H2 95% Ar. The solubility limit the filling voids in was found to be close 0.22. Synchrotron X-ray diffraction refinement = 0.2 sample showed that is located classic rattler site has substantially larger factor than those Co Sb. electrical resistivity, Seebeck coefficients,...
We report on the effects of spin fluctuations, magnetic ordering, and external field dielectric constant ferromagnet SeCuO3, antiferromagnet TeCuO3. A model based coupling between uniform polarization q-dependent spin-spin correlation function is presented to explain different behaviors for these isostructural compounds. The large magnetocapacitance near transition temperature in SeCuO3 suggests routes enhancing magnetodielectric response practical applications.
Electrical and thermal transport properties of synthetic tetrahedrites Cu10TM2Sb4S13 (TM = Mn, Fe, Co, Ni, Zn) the solid solution Cu12–xMnxSb4S13 (0 ≤ x 2) have been studied in context thermoelectric performance. Among these materials, parent compound Cu12Sb4S13 exhibits highest power factor, which is primarily derived from a high electrical conductivity. All substituted derivatives display significant uniform reduction Within TM series, Mn-substituted sample displays ZT (0.8 at 575 K)....
We show that trivalent manganese, Mn(3+), imparts an intense blue color to oxides when it is introduced at dilution in trigonal bipyramidal coordination. Our optical measurements and first-principles density functional theory calculations indicate the results from absorption red/green region. This due turn a symmetry-allowed transition between valence-band maximum, composed of Mn 3d(x(2)-y(2),xy) states strongly hybridized with O 2p(x,y) states, narrow 3d(z(2))-based conduction-band minimum....
The severe urban heat island effect emphasizes the heightened importance of reducing building energy consumption. Cool pigments with higher near-infrared reflectivity contribute to overall coating performance building. In this work, a novel intense blue pigment superior infrared reflectance based on Ni-doped Zn2SiO4 was successfully synthesized via simple solid-state method. crystal structure, oxidation states, and optical properties are analyzed. state Ni confirmed be +2 using magnetic...
The atomic positional correlations in superconducting ${\mathrm{Tl}}_{2}$${\mathrm{Ba}}_{2}$Ca${\mathrm{Cu}}_{2}$${\mathrm{O}}_{8}$ were studied by pair-distribution-function analysis of the pulsed-neutron scattering data. results show for first time strongly correlated local displacements both thallium and oxygen atoms Tl-O plane from high-symmetry crystallographic sites. As a consequence Tl form chains or pairs accompanied displacement nearby atoms, resulting locally orthorhombic order....
We present the thermal conductivity $(\ensuremath{\kappa})$ of several manganite perovskite compounds at temperatures 10--350 K and fields up to 6 T. In metallic phase, $\ensuremath{\kappa}$ behaves as expected for a crystalline solid. high-temperature insulating however, $d\ensuremath{\kappa}/dT>0$, behavior an amorphous Unlike solids, $d\ensuremath{\kappa}/dT>0$ here is related not quenched structural disorder but rather unusually large dynamic lattice distortions accompanying charge...
The bulk magnetic susceptibility of ${\mathrm{Y}}_{2}$${\mathrm{Mn}}_{2}$${\mathrm{O}}_{7}$ is suggestive ferromagnetic order, with ${\mathit{FTHETA}}_{\mathit{C}}$=+41(2) K, and an apparent ${\mathit{T}}_{\mathit{c}}$=20 K. However, both dc ac data show a broad maximum near 7 which frequency field dependent. Heat-capacity studies down to 2 K no evidence for long-range order. Neutron-scattering indicate the presence antiferromagnetic (first neighbors) (second third short-range correlations....
Epitaxial thin films of La2NiMnO6, a ferromagnetic semiconductor, have been fabricated on different substrates by pulsed laser deposition. The x-ray diffraction and Raman scattering observations reveal that the are single crystalline an orthorhombic structure. magnetic properties films, including coercive field, remanent magnetization, Curie temperature, strongly dependent choice substrate. optimized exhibit moment 4.63μB∕f.u. at 5K, with temperature close to 280K. film characteristics...
Two uranyl phenylphosphonates, [UO2(HO3PC6H5)2(H2O)]2·8H2O (1) and UO2(HO3PC6H5)2·2CH3CH2OH (2), have been synthesized their structures solved by single-crystal methods. Both compounds crystallize in the triclinic space group P1̄. Unit cell parameters are a = 11.724(4) Å, b 16.676(8) c 11.375(2) α 101.61(5)°, β 106.76(3)°, γ 102.57(4)°, Z 2 for compound 1 9.332(6) 11.48(1) 5.672(2) 98.98(6)°, 92.78(5)°, 108.54(5)°, 2. In both metal to phosphonate ratio is 1:2, they form linear chains. Each...