Generation of a Hetero Spin Complex from Iron(II) Iodide with Redox Active Acenaphthene-1,2-Diimine

The reaction of the redox active 1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene (dpp-BIAN) and iron(II) iodide in acetonitrile led to a new complex [(dpp-BIAN)FeIII2] (1). Molecular structure of 1 was determined by the single crystal X-ray diffraction analysis. The spin state of the iron cation in complex 1 at room temperature and the magnetic behavior of 1 in the temperature range of 2–300 K were studied using Mossbauer spectroscopy and magnetic susceptibility measurements, respectively. The neutral character of dpp-BIAN in 1 was confirmed by IR and UV spectroscopy. The electrochemistry of 1 was studied in solution and solid state using cyclic voltammetry. The generation of the radical anion form of the dpp-BIAN ligand upon reduction of 1 in a CH2Cl2 solution was monitored by EPR spectroscopy.

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PHASE STRUCTURE, PIEZOELECTRIC AND MULTIFERRIOC BEHAVIOR OF (K0.48Na0.52)NbO3-Co2O3 PIEZOELECTRIC CERAMICS

Functional Materials Letters ◽

10.1142/s1793604711002081 ◽

2011 ◽

Vol 04 (03) ◽

pp. 225-229 ◽

Cited By ~ 6

Author(s):

WENJUAN WU ◽

DINGQUAN XIAO ◽

JIAGANG WU ◽

JING LI ◽

JIANGUO ZHU

Keyword(s):

Room Temperature ◽

Sintering Temperature ◽

Magnetic Behavior ◽

Orthorhombic Phase ◽

Piezoelectric Ceramics ◽

X Ray Diffraction ◽

Two Phase ◽

X Ray ◽

Solid State Sintering ◽

Sintering Method

( K 0.48 Na 0.52) NbO 3-x% Co 2 O 3 (x = 0, 0.03 and 0.05) (KNN-x% Co2O3 ) lead-free piezoelectric ceramics were prepared by the conventional solid-state sintering method. An orthorhombic phase was observed for all KNN-x% Co2O3 ceramics at room temperature, and two phase transitions were confirmed by the high temperature X-ray diffraction and the temperature dependence of the dielectric constant. The Co2O3 greatly improves the density and decreases the sintering temperature of KNN ceramics. The KNN-0.05 mol%Co2O3 ceramic exhibits good properties (d33 = 120 pC/N , k p = 0.41, Q m = 213 and T c = 407°C) and a good age stability. The multiferroic behavior was also observed at room temperature for the KNN-0.05 mol%Co2O3 ceramic, as confirmed by P–E loops and magnetic behavior.

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Czochralski Growth, Magnetic Properties and Faraday Characteristics of CeAlO3 Crystals

Crystals ◽

10.3390/cryst9050245 ◽

2019 ◽

Vol 9 (5) ◽

pp. 245 ◽

Cited By ~ 5

Author(s):

Feiyun Guo ◽

Qiyuan Li ◽

Huaimin Zhang ◽

Xiongsheng Yang ◽

Zhen Tao ◽

...

Keyword(s):

Room Temperature ◽

Magnetic Circular Dichroism ◽

Structure Refinement ◽

Magnetic Behavior ◽

Czochralski Method ◽

Czochralski Growth ◽

X Ray Diffraction ◽

X Ray ◽

Van Vleck ◽

Abnormal Magnetic Behavior

CeAlO3 crystals were grown in different growth atmospheres by the Czochralski method. The lattice parameters and space group of CeAlO3 crystal were determined by Rietveld structure refinement of X-ray diffraction (XRD) data. The influence of Ce4+ ions in the crystal on the transmittance and crystal color was confirmed by XPS analysis. Magnetization curve at room temperature and temperature dependencies of the magnetic susceptibility in two different directions were measured, indicating that CeAlO3 crystal has remarkable magnetic anisotropy and there is an abnormal magnetic behavior in the vertical <001> direction in the temperature range of 50–150 K. Faraday characteristics of CeAlO3 crystal were investigated at room temperature. Verdet constants of CeAlO3 at 532, 635 and 1064 nm are about 2.1 times as large as those of CeF3. The reason of large Verdet constants was analyzed based on the Van Vleck–Hebb theory and the magnetic circular dichroism (MCD) spectrum.

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Highest Connectivity in a Purely Inorganic 3D Compound Based on Paradodecatungstate-B Clusters: Synthesis and Magnetic Properties

Zeitschrift für Naturforschung B ◽

10.1515/znb-2009-0706 ◽

2009 ◽

Vol 64 (7) ◽

pp. 809-814 ◽

Cited By ~ 2

Author(s):

Chun-Jing Zhang ◽

Hai-Jun Pang ◽

Ya-Guang Chen

Keyword(s):

Magnetic Properties ◽

Single Crystal ◽

Elemental Analysis ◽

Uv Spectroscopy ◽

Three Dimensional ◽

X Ray Diffraction ◽

X Ray ◽

Simulation Procedure ◽

3D Framework ◽

Ir And Uv Spectroscopy

A new paradodecatungstate-B compound, [{Co(H2O)4}4(H4W12O42)]·10H2O (1) of the polyoxometalate series has been synthesized and characterized by elemental analysis, IR and UV spectroscopy, TG analysis, and single-crystal X-ray diffraction. Compound 1 exhibits a unique 8- connected three-dimensional (3D) framework with a (42 · 820 · 126) topology. Moreover, 1 displays antiferromagnetic interactions in the 2 - 300 K temperature range, well reproduced by a simulation procedure.

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New Coordination Compounds Derived from Nitrone Ligands: Copper(II) Complexes with 8-Hydroxyquinoline-2-carbaldehyde- and Pyridine-2-carbaldehyde-N-methylnitrones

Zeitschrift für Naturforschung B ◽

10.1515/znb-2001-1203 ◽

2001 ◽

Vol 56 (12) ◽

pp. 1264-1270 ◽

Cited By ~ 7

Author(s):

Elena G. Petkova ◽

Konstantin V. Domasevitch ◽

Marian V. Gorichko ◽

Vera Y. Zub ◽

Rostislav D. Lampeka

Keyword(s):

Coordination Compounds ◽

Copper Ions ◽

Uv Spectroscopy ◽

X Ray Diffraction ◽

X Ray ◽

Octahedral Environment ◽

Distorted Octahedral ◽

Hydroxy Groups ◽

Ir And Uv Spectroscopy ◽

Oxygen Atoms

Abstract New copper(II) complexes with 8-hydroxyquinoline-2-carbaldehyde-N-methylnitrone (HL1) (1) and pyridine-2-carbaldehyde-N-methylnitrone (L2) (2) have been synthesized. The crystal structure of compound 1 consists of binuclear molecules Cu2(L1)2(NO3)2 with the oxygen atoms of the hydroxy groups acting as bridges between the copper ions. The nitrone ligand in 1 is coordinated in a tridentate fashion forming five-and six-membered chelate rings, and the copper ions have a square-pyramidal environment with the bridging oxygen atoms in apical positions. In compound 2 Cu(L2)2(NO3)2, the copper atom adopts a distorted octahedral environment with bidentately coordinated nitrone ligands. In both cases the nitrone groups are involved in coordination via the oxygen atom. Compounds 1 and 2 have been studied by EPR, UV-VIS and IR spectroscopy. The free nitrone HL1 has also been studied by X-ray diffraction as well as by IR and UV spectroscopy.

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Electron Microscopy of Human Gallstones

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100065523 ◽

1971 ◽

Vol 29 ◽

pp. 296-297

Author(s):

C. Wolpers ◽

R. Blaschke

Keyword(s):

Electron Microscopy ◽

Room Temperature ◽

Bile Pigment ◽

X Ray Diffraction ◽

Triclinic Crystal System ◽

X Ray ◽

Follow Up Study ◽

Infra Red ◽

Main Components

Scanning microscopy was used to study the surface of human gallstones and the surface of fractures. The specimens were obtained by operation, washed with water, dried at room temperature and shadowcasted with carbon and aluminum. Most of the specimens belong to patients from a series of X-ray follow-up study, examined during the last twenty years. So it was possible to evaluate approximately the age of these gallstones and to get information on the intensity of growing and solving.Cholesterol, a group of bile pigment substances and different salts of calcium, are the main components of human gallstones. By X-ray diffraction technique, infra-red spectroscopy and by chemical analysis it was demonstrated that all three components can be found in any gallstone. In the presence of water cholesterol crystallizes in pane-like plates of the triclinic crystal system.

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Electron Microscope study of commensurate-incommensurate phase transition in BaZnGeO4

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100173996 ◽

1990 ◽

Vol 48 (4) ◽

pp. 172-173

Author(s):

Naoki Yamamoto ◽

Makoto Kikuchi ◽

Tooru Atake ◽

Akihiro Hamano ◽

Yasutoshi Saito

Keyword(s):

Phase Transition ◽

Electron Microscope Study ◽

Room Temperature ◽

Hexagonal Lattice ◽

Ferroelectric Materials ◽

Temperature Phase ◽

X Ray Diffraction ◽

X Ray ◽

Periodic Arrays ◽

Modulation Wave Vector

BaZnGeO4 undergoes many phase transitions from I to V phase. The highest temperature phase I has a BaAl2O4 type structure with a hexagonal lattice. Recent X-ray diffraction study showed that the incommensurate (IC) lattice modulation appears along the c axis in the III and IV phases with a period of about 4c, and a commensurate (C) phase with a modulated period of 4c exists between the III and IV phases in the narrow temperature region (—58°C to —47°C on cooling), called the III' phase. The modulations in the IC phases are considered displacive type, but the detailed structures have not been studied. It is also not clear whether the modulation changes into periodic arrays of discommensurations (DC’s) near the III-III' and IV-V phase transition temperature as found in the ferroelectric materials such as Rb2ZnCl4.At room temperature (III phase) satellite reflections were seen around the fundamental reflections in a diffraction pattern (Fig.1) and they aligned along a certain direction deviated from the c* direction, which indicates that the modulation wave vector q tilts from the c* axis. The tilt angle is about 2 degree at room temperature and depends on temperature.

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Xenon Trioxide Adducts of O-Donor Ligands; [(CH3)2CO]3XeO3, [(CH3)2SO]3(XeO3)2, (C5H5NO)3(XeO3)2, and [(C6H5)3PO]2XeO3

10.26434/chemrxiv.7092263.v1 ◽

2018 ◽

Author(s):

Katherine Marczenko ◽

James Goettel ◽

Gary Schrobilgen

Keyword(s):

Room Temperature ◽

Triphenylphosphine Oxide ◽

Donor Ligands ◽

Mechanical Shock ◽

X Ray Diffraction ◽

X Ray ◽

Oxygen Coordination ◽

Xenon Trioxide ◽

Distorted Octahedra ◽

Coordination Spheres

Oxygen coordination to the Xe(VI) atom of XeO3 was observed in its adducts with triphenylphosphine oxide, dimethylsulfoxide, pyridine-N-oxide, and acetone. The crystalline adducts were characterized by low-temperature, single-crystal X-ray diffraction and Raman spectroscopy. Unlike solid XeO3, which detonates when mechanically or thermally shocked, the solid [(C6H5)3PO]2XeO3, [(CH3)2SO]3(XeO3)2, and (C5H5NO)3(XeO3)2 adducts are insensitive to mechanical shock, but undergo rapid deflagration when ignited by a flame. Both [(C6H5)3PO]2XeO3 and (C5H5NO)3(XeO3)2 are air-stable whereas [(CH3)2SO]3(XeO3)2 slowly decomposes over several days and [(CH3)2CO]3XeO3 undergoes adduct dissociation at room temperature. The xenon coordination sphere of [(C6H5)3PO]2XeO3 is a distorted square pyramid which provides the first example of a five-coordinate XeO3 adduct. The xenon coordination spheres of the remaining adducts are distorted octahedra comprised of three Xe---O secondary contacts that are approximately trans to the primary Xe–O bonds of XeO3. Quantum-chemical calculations were used to assess the Xe---O adduct bonds, which are predominantly electrostatic σ-hole bonds between the nucleophilic oxygen atoms of the bases and the σ-holes of the xenon atoms.

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Effect of trytophan as dopant on potassium acid phthalate single crystals

10.31221/osf.io/cn28k ◽

2019 ◽

Author(s):

Chem Int

Keyword(s):

Single Crystals ◽

Room Temperature ◽

Visible Region ◽

X Ray Diffraction ◽

X Ray ◽

Slow Evaporation Technique ◽

Absorption Studies ◽

Evaporation Technique ◽

Potassium Acid Phthalate ◽

Acid Phthalate

Optically transparent single crystals of potassium acid phthalate (KAP, 0.5 g) 0.05 g and 0.1 g (1 and 2 mol %) trytophan were grown in aqueous solution by slow evaporation technique at room temperature. Single crystal X- ray diffraction analysis confirmed the changes in the lattice parameters of the doped crystals. The presence of functional groups in the crystal lattice has been determined qualitatively by FTIR analysis. Optical absorption studies revealed that the doped crystals possess very low absorption in the entire visible region. The dielectric constant has been studied as a function of frequency for the doped crystals. The thermal stability was evaluated by TG-DSC analysis.

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Structural and Enhanced Optical Properties of Stabilized γ‒Bi2O3 Nanoparticles: Effect of Oxygen Ion Vacancies

Nanomaterials ◽

10.3390/nano10061023 ◽

2020 ◽

Vol 10 (6) ◽

pp. 1023 ◽

Cited By ~ 2

Author(s):

Ashish Chhaganlal Gandhi ◽

Chia-Liang Cheng ◽

Sheng Yun Wu

Keyword(s):

Room Temperature ◽

Excess Oxygen ◽

Ambient Atmosphere ◽

Photoluminescence Spectra ◽

X Ray Diffraction ◽

X Ray ◽

Band Emission ◽

Oxygen Ion ◽

Integrated Intensity ◽

Effect Of Oxygen

We report the synthesis of room temperature (RT) stabilized γ–Bi2O3 nanoparticles (NPs) at the expense of metallic Bi NPs through annealing in an ambient atmosphere. RT stability of the metastable γ–Bi2O3 NPs is confirmed using synchrotron radiation powder X-ray diffraction and Raman spectroscopy. γ–Bi2O3 NPs exhibited a strong red-band emission peaking at ~701 nm, covering 81% integrated intensity of photoluminescence spectra. Our findings suggest that the RT stabilization and enhanced red-band emission of γ‒Bi2O3 is mediated by excess oxygen ion vacancies generated at the octahedral O(2) sites during the annealing process.

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Mechanical Alloying Behavior in the Nb-Si, Ta-Si, and Nb-Ta-Si Systems

MRS Proceedings ◽

10.1557/proc-133-415 ◽

1988 ◽

Vol 133 ◽

Cited By ~ 3

Author(s):

K. S. Kumar ◽

S. K. Mannan

Keyword(s):

High Temperature ◽

Mechanical Alloying ◽

Mechanical Milling ◽

Room Temperature ◽

Crystalline Compound ◽

X Ray Diffraction ◽

X Ray ◽

Β Phase ◽

Α Phase

ABSTRACTThe mechanical alloying behavior of elemental powders in the Nb-Si, Ta-Si, and Nb-Ta-Si systems was examined via X-ray diffraction. The line compounds NbSi2 and TaSi2 form as crystalline compounds rather than amorphous products, but Nb5Si3 and Ta5Si3, although chemically analogous, respond very differently to mechanical milling. The Ta5Si3 composition goes directly from elemental powders to an amorphous product, whereas Nb5Si3 forms as a crystalline compound. The Nb5Si3 compound consists of both the tetragonal room-temperature α phase (c/a = 1.8) and the tetragonal high-temperature β phase (c/a = 0.5). Substituting increasing amounts of Ta for Nb in Nb5Si3 initially stabilizes the α-Nb5Si3 structure preferentially, and subsequently inhibits the formation of a crystalline compound.

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