Synthesis and Characterization of Pb(Fe1/2Ta1/2)O3

2007 ◽  
Vol 1034 ◽  
Author(s):  
Ricardo Martinez ◽  
R. Palai ◽  
R.S. Katiyar

AbstractLead iron tantalate Pb(Fe1/2Ta1/2)O3 (PFT) is a compound derived of general formula Pb(BIxBII1-x)O3 wherein x=1/2. In this work synthesis, sintering processes, dielectric, electrical, magnetic measurement, and Raman spectroscopy properties of PFT ceramics are described. The dielectric properties of PFT showed typical relaxor behaviors. We saw that ferroelectric and magnetic orders coexist in PFT at room temperature.

2013 ◽  
Vol 10 (3) ◽  
pp. 650-657
Author(s):  
Baghdad Science Journal

This research involves the preparation of new ligands 1,1,2,2- tetrakis (sodium acetate thio)ethylene(L1) and 1,1,2- tris(sodiumacetatethio) ethylene(L2), through the reaction of disodium thioglycolate) with tetra chloro ethylene or tri chloro ethylene in (1:4) or (1:3) moler ratio . Homodinucliar complexes of general formlu [M2(L1)] and [M2(L2)ClH2O] , when M= Co(II), Ni(II), Cu (II) and Zn(II) also mono nuclear complexes of general formula [M(L2)] . The prepared complexes were characterized using spectral method (UV/Visible/ IR) , metal content analysis , magnetic and atomic measurements . The spectral and magnetic measurement indicats that some complexes have tetrahedral or square planar complexes environtment .


1987 ◽  
Vol 65 (9) ◽  
pp. 2305-2311 ◽  
Author(s):  
Raj K. Chadha ◽  
John E. Drake ◽  
Neil T. McManus ◽  
Anil Mislankar

Complexes of the general formula [HgX2(Me3MCH2SeMe)]2, where M = Si, Ge; X = Cl, Br, I, have been prepared and characterized by 1H nuclear magnetic resonance and Raman spectroscopy. Crystal structures of [HgX2(Me3SiCH2SeMe)]2, where X = Cl, Br, and I (1, 2, and 3 respectively), show that they have centrosymmetric dinuclear structures. The crystals of 1 and 2 are monoclinic, while those of 3 are triclinic. For 1: P21/c, a = 14.235(11), b = 6.551(6), c = 14.211(9) Å, β = 117.33(5)°, Z = 2, and R = 0.0560. For 2: P21/c, a = 14.329(6), b = 6.695(2), c = 14.819(4) Å, β = 118.47(2)°, Z = 2, and R = 0.0540. For 3: [Formula: see text], a = 7.651(2), b = 8.387(2), c = 12.321(4) Å, α = 90.07(2), β = 91.80(2), γ = 116.02(2)°, Z = 1, and R = 0.0565. All three complexes show the expected pseudotetrahedral geometry about mercury. The stereochemical differences arise in the arrangement of the bulky trimethylsilylmethyl groups, which in the HgI2 adduct are rotated away from the centre of the molecule but which in the HgCl2 and HgBr2 adducts are turned towards the centre. These are the first dinuclear structures reported of HgBr2 and HgI2 adducts since it was demonstrated 46 years ago by Evans etal. that [HgBr2(AsBu3)]2 was present in [HgBr2(AsBu3)2•HgBr2].


RSC Advances ◽  
2021 ◽  
Vol 11 (22) ◽  
pp. 13245-13255
Author(s):  
Mehdi Davoodi ◽  
Fatemeh Davar ◽  
Mohammad R. Rezayat ◽  
Mohammad T. Jafari ◽  
Mehdi Bazarganipour ◽  
...  

New nanocomposite of zeolitic imidazolate framework-67@magnesium aluminate spinel (ZIF-67@MgAl2O4) has been fabricated by a simple method at room temperature with different weight ratios.


2017 ◽  
Vol 437 ◽  
pp. 51-61 ◽  
Author(s):  
Benjaporn Yotburut ◽  
Prasit Thongbai ◽  
Teerapon Yamwong ◽  
Santi Maensiri

1990 ◽  
Vol 5 (11) ◽  
pp. 2718-2722 ◽  
Author(s):  
K. B. R. Varma ◽  
G. N. Subbanna ◽  
T. N. Guru ◽  
C. N. R. Rao

Bi2VO5.5 (Bi4O11), which is the vanadium analog of the first member of the Aurivillius family of oxides of the general formula Bi2An−1BnO3n+3, has been prepared and characterized. The vanadate has the expected layered structure and is ferroelectric with a Curie temperature of 720 K. While we have not been able to synthesize the vanadium analog of the n = 2 member of the Aurivillius family, we have examined the structure and properties of a vanadate of the composition Bi2V3O9.


2013 ◽  
Vol 2013 ◽  
pp. 1-7 ◽  
Author(s):  
Evelyn Carolina Martínez Ceballos ◽  
Ricardo Vera Graziano ◽  
Gonzalo Martínez Barrera ◽  
Oscar Olea Mejía

Poly(dichlorophosphazene) was prepared by melt ring-opening polymerization of the hexachlorocyclotriphosphazene. Poly[bis(2-hydroxyethyl-methacrylate)-phosphazene] and poly[(2-hydroxyethyl-methacrylate)-graft-poly(lactic-acid)-phosphazene] were obtained by nucleophilic condensation reactions at different concentrations of the substituents. The properties of the synthesized copolymers were assessed by FTIR,1H-NMR and31P-NMR, thermal analysis (DSC-TGA), and electron microscopy (SEM). The copolymers have a block structure and show twoTg's below room temperature. They are stable up to a temperature of 100°C. The type of the substituents attached to the PZ backbone determines the morphology of the polymers.


Inorganics ◽  
2018 ◽  
Vol 6 (3) ◽  
pp. 97 ◽  
Author(s):  
Marie Gaschard ◽  
Farzaneh Nehzat ◽  
Thomas Cheminel ◽  
Bruno Therrien

The synthesis and characterization of three metalla-rectangles of the general formula [Ru4(η6-p-cymene)4(μ4-clip)2(μ2-Lanthr)2][CF3SO3]4 (Lanthr: 9,10-bis(3,3’-ethynylpyridyl) anthracene; clip = oxa: oxalato; dobq: 2,5-dioxido-1,4-benzoquinonato; donq: 5,8-dioxido-1,4-naphthoquinonato) are presented. The molecular structure of the metalla-rectangle [Ru4(η6-p-cymene)4(μ4-oxa)2(μ2-Lanthr)2]4+ has been confirmed by the single-crystal X-ray structure analysis of [Ru4(η6-p-cymene)4(μ4-oxa)2(μ2-Lanthr)2][CF3SO3]4 · 4 acetone (A2 · 4 acetone), thus showing the anthracene moieties to be available for reaction with oxygen. While the formation of the endoperoxide form of Lanthr was observed in solution upon white light irradiation, the same reaction does not occur when Lanthr is part of the metalla-assemblies.


2020 ◽  
Author(s):  
Joel D. Smith ◽  
George Durrant ◽  
Daniel Ess ◽  
Warren Piers

<div>The synthesis and characterization of an iridium polyhydride complex (Ir-H4)</div><div>supported by an electron-rich PCP framework is described. This complex readily loses molecular</div><div>hydrogen allowing for rapid room temperature hydrogen isotope exchange (HIE) at the hydridic</div><div>positions and the α-C-H site of the ligand with deuterated solvents such as benzene-d6, toluene-d8</div><div>and THF-d8. The removal of 1-2 equivalents of molecular H2 forms unsaturated iridium carbene</div><div>trihydride (Ir-H3) or monohydride (Ir-H) compounds that are able to create further unsaturation</div><div>by reversibly transferring a hydride to the ligand carbene carbon. These species are highly active</div><div>hydrogen isotope exchange (HIE) catalysts using C6D6 or D2O as deuterium sources for the</div><div>deuteration of a variety of substrates. By modifying conditions to influence the Ir-Hn speciation,</div><div>deuteration levels can range from near exhaustive to selective only for sterically accessible sites.</div><div>Preparative level deuterations of select substrates were performed allowing for procurement of</div><div>>95% deuterated compounds in excellent isolated yields; the catalyst can be regenerated by</div><div>treatment of residues with H2 and is still active for further reactions.</div>


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