scholarly journals Synthesis, Crystal Structure and Electrical Properties of the Molybdenum Oxide Na1.92Mg2.04Mo3O12

2013 ◽  
Vol 2013 ◽  
pp. 1-6 ◽  
Author(s):  
Ennajeh Ines ◽  
Mohamed Faouzi Zid ◽  
Ahmed Driss
Keyword(s):  
Crystal Structure ◽  
Molybdenum Oxide ◽  
Three Dimensional ◽  
Ac Impedance Spectroscopy ◽  
Unit Cell Parameters ◽  
Solid State Method ◽  
Cell Parameters ◽  
Triclinic System ◽  
State Method ◽  
Mixed Framework

New molybdenum oxide Na1.92Mg2.04Mo3O12 has been synthesized by the solid state method. The title compound crystallizes in the triclinic system (space group P-1). The unit cell parameters are a = 6.9660(7) Å, b = 8.6352(8) Å, c = 10.2501(8) Å, α = 106.938(1)°, β = 104.825(1)°, γ = 103.206(1)°, V = 538.72(9) Å3, and Z = 2. The compound is isotypical to Ag2M2(MoO4)3 (M = Zn, Mg, Co, Mn). The structure can be described as a three-dimensional anionic mixed framework of MoO4 tetrahedra and pairs of Mg2O10 octahedra sharing common edges. The Na+ ions are disordered and located in the voids forming infinite channels running along the direction [100]. The electrical conductivity investigated from 693 K to 793 K by AC impedance spectroscopy is low (3.01×10−7 S cm−1 at 683 K).

Crystal structure refinement of new vanadates Ca8−xPbxCdBi(VO4)7

2017 ◽  
Vol 32 (S1) ◽  
pp. S106-S109 ◽  
Author(s):  
Daria Petrova ◽  
Dina Deyneko ◽  
Sergey Stefanovich ◽  
Bogdan Lazoryak
Keyword(s):  
Crystal Structure ◽  
Solid State ◽  
Second Harmonic ◽  
Structure Refinement ◽  
Polar Space ◽  
Crystal Structure Refinement ◽  
Unit Cell Parameters ◽  
Solid State Method ◽  
Cell Parameters ◽  
State Method

New Ca8−xPbxCdBi(VO4)7 with the whitlockite-type structure were prepared by a standard solid-state method in air. Le Bail decomposition was used to determine unit-cell parameters. Structural refining was carried out by Rietveld's method. It is found that Bi3+ cations located partially in M1 and M2 sites along with calcium, while M3 site is settled in half by Pb2+-ions. Second-harmonic generation demonstrate highest non-linear optical activity and along with dielectric investigations indicate polar space group R3c.

Redefinition of satimolite

2018 ◽  
Vol 82 (5) ◽  
pp. 1033-1047 ◽  
Author(s):  
Igor V. Pekov ◽  
Natalia V. Zubkova ◽  
Dmitry A. Ksenofontov ◽  
Nikita V. Chukanov ◽  
Vasiliy O. Yapaskurt ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Rietveld Method ◽  
Three Dimensional ◽  
Direct Methods ◽  
Salt Dome ◽  
Unit Cell ◽  
Unit Cell Parameters ◽  
Cell Parameters ◽  
Octahedral Clusters

ABSTRACTThe borate mineral satimolite, which was first described in 1969 and remained poorly-studied until now, has been re-investigated (electron microprobe analysis, single-crystal and powder X-ray diffraction studies, crystal-structure determination, infrared spectroscopy) and redefined based on the novel data obtained for the holotype material from the Satimola salt dome and a recently found sample from the Chelkar salt dome, both in North Caspian Region, Western Kazakhstan. The revised idealized formula of satimolite is KNa2(Al5Mg2)[B12O18(OH)12](OH)6Cl4·4H2O (Z = 3). The mineral is trigonal, space group R$\bar{3}$m, unit-cell parameters are: a = 15.1431(8), c = 14.4558(14) Å and V = 2870.8(4) Å3 (Satimola) and a = 15.1406(4), c = 14.3794(9) Å and V = 2854.7(2) Å3 (Chelkar). The crystal system and unit-cell parameters are quite different from those reported previously. The crystal structure of the sample from Chelkar was solved based on single-crystal data (direct methods, R = 0.0814) and the structure of the holotype from Satimola was refined on a powder sample by the Rietveld method (Rp = 0.0563, Rwp = 0.0761 and Rall = 0.0667). The structure of satimolite is unique for minerals. It contains 12-membered borate rings [B12O18(OH)12] in which BO3 triangles alternate with BO2(OH)2 tetrahedra sharing common vertices, and octahedral clusters [M7O6(OH)18] with M = Al5Mg2 in the ideal case, with sharing of corners between rings and clusters to form a three-dimensional heteropolyhedral framework. Each borate ring is connected with six octahedral clusters: three under the ring and three over the ring. Large ellipsoidal cages in the framework host Na and K cations, Cl anions and H2O molecules.

scholarly journals Synthesis, Crystal Structure, and Electrical Properties of a New Molybdylarsenate LiNa5K3Mo11As3O45

2014 ◽  
Vol 2014 ◽  
pp. 1-9
Author(s):  
Hamadi Hamza ◽  
Mohamed Faouzi Zid ◽  
Ahmed Driss
Keyword(s):  
Crystal Structure ◽  
Electrical Conductivity ◽  
Solid State ◽  
Inorganic Compound ◽  
X Ray Diffraction ◽  
Solid State Method ◽  
One Dimensional ◽  
X Ray ◽  
Triclinic System ◽  
State Method

LiNa5K3Mo11As3O45 is a new inorganic compound. It was synthesized by a solid state method. The crystal structure has been studied by single crystal X-ray analysis. The R-values reached 2.8%. The title compound crystallizes in the triclinic system, space group P-1, with a = 10.550 (2) Å, b = 11.723 (2) Å, c = 17.469 (3) Å, α = 102.35 (3)°, β = 87.61 (2)°, and γ = 111.03 (3)°. The anionic unit [Mo11As3O45]9− is formed by nine MoO6 octahedra, two MoO5 trigonal bipyramids, and three AsO4 tetrahedra. The association of [Mo11As3O45]9− units, running along [010], leads to a one-dimensional framework. Li, K, and Na are located in the space surrounding the anionic ribbons. This material was characterized by SEM microscopy, IR spectroscopy, and powder X-ray diffraction. The electrical conductivity was investigated from 528 K to 673 K by impedance complex followed by DSC spectroscopy.

scholarly journals Synthesis, Crystal structure, Vibrational, Optical and Dielectric properties Of 2-(2-Aminoethyl)-1-methylpyrrolidinum chloride hexachlorobismuthate (III) monohydrate [C7H18N2]2ClBiCl6.H2O

2013 ◽  
Vol 9 (3) ◽  
pp. 2005-2022 ◽  
Author(s):  
Fayçal Ben Tahar ◽  
Chakib Hrizi ◽  
Slaheddine Chaabouni ◽  
Nassira Chniba-Boudjada ◽  
Nicolas Ratel Ramond ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Dielectric Properties ◽  
Room Temperature ◽  
Three Dimensional ◽  
Free Water ◽  
Unit Cell ◽  
Water Molecules ◽  
Unit Cell Parameters ◽  
Cell Parameters ◽  
Vis Spectroscopy

Synthesis, crystal structure, vibrational and dielectric properties of [C7H18N2]2ClBiCl6.H2O are reported. The compound crystallizes at room temperature in the orthorhombic system, space group P212121, with the following unit cell parameters : a = 7.5500(6) Å, b = 18.3780(2) Å, c = 19.8980(13) Å, V = 2760.9(4) Å3 and four molecules per unit cell. The structure has been solved by three-dimensional Patterson synthesis and refined by least-squares analysis (R1 = 0.0463, wR2 = 0.0764). The crystal structure of the title compound, [C7H18N2]2ClBiCl6.H2O consists of 2-(2-Aminoethyl)-1-methylpyrrolidinium cations, [BiCl6]3- anions, Cl- anions and free water molecules. The Bi(III) cation is coordinated by six Cl- anions in slightly distorsed octahedral geometry. In the crystal, extensive intermolecular N-H…Cl hydrogen bonds occur. The charge-transfer (CT) interactions between 2-(2-Aminoethyl)-1-methylpyrrolidinium cation and the anionic hosts have been revealed by structural analysis and UV-vis spectroscopy. The dielectric properties have been investigated at temperature range from 100 to 300 K at various frequencies (1 KHz – 1 MHz). The evolution of dielectric constant as a function of temperature and frequency of pellet has been investigated in order to determine some related parameters.

scholarly journals Crystal Structure and Molecular Mechanics Modelling of 2-(4-Amino-3-benzyl-2-thioxo-2,3-dihydrothiazol-5-yl)benzoxazole

2014 ◽  
Vol 2014 ◽  
pp. 1-5 ◽  
Author(s):  
Ahmed F. Mabied ◽  
Elsayed M. Shalaby ◽  
Hamdia A. Zayed ◽  
Esmat El-Kholy ◽  
Ibrahim S. A. Farag
Keyword(s):  
Crystal Structure ◽  
Molecular Mechanics ◽  
Phenyl Ring ◽  
Molecular Geometry ◽  
Maximum Deviation ◽  
Unit Cell Parameters ◽  
Intermolecular Hydrogen Bonds ◽  
Cell Parameters ◽  
Triclinic System ◽  
Single Crystal Analysis

The crystal structure of the title compound, 2-(4-amino-3-benzyl-2-thioxo-2,3-dihydrothiazol-5-yl)benzoxazole, was determined. The crystal has P1 space group and triclinic system with unit cell parameters a = 5.174(3) Å, b = 6.411(6) Å, c = 12.369(10) Å, α = 86.021(4)°, β = 84.384(5)°, and γ = 77.191(5)°. The structure consists of benzoxazole group connected with benzyl via thiazole (attached with amino and thione). Benzoxazole and thiazole rings are almost planar (maximum deviation at C1, −0.013(3) Å, and C10, 0.0041(3) Å, resp.). The phenyl ring is nearly perpendicular to both thiazole and benzoxazole rings. A network of intermolecular hydrogen bonds and intermolecular interactions stabilizes the structure, forming parallel layers. The molecular geometry obtained using single crystal analysis is discussed along with results of the molecular mechanics modeling (MM), and the results showed the same cis conformation between benzoxazole nitrogen atom and the amino group.

scholarly journals Synthesis, Crystal structure of hepta (pyridinium) bis (hexachlorobismuthate (III)) nitrate [C5H6N]7(BiCl6)2(NO3)

2013 ◽  
Vol 9 (2) ◽  
pp. 1975-1987
Author(s):  
Ben Tahar Fayçal ◽  
Perez Olivier ◽  
Slaheddine Chaabouni
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Title Compound ◽  
Room Temperature ◽  
Three Dimensional ◽  
Unit Cell ◽  
Unit Cell Parameters ◽  
Monoclinic System ◽  
Cell Parameters ◽  
Dimensional Network

An hepta (pyridinium) bis (hexachlorobismuthate (III)) nitrate, (C5H6N)7(BiCl6)2(NO3) crystallizes at room temperature in the monoclinic system, space group P21/n, with the following unit-cell parameters: a = 9.555(1) Å, b = 16.847(1) Å, c = 32.522(1) Å, β = 94.37° , V = 5219.8 Å3 and four molecules per unit cell. Its crystal structure was determined and refined down to R1 = 0.0504, wR2 = 0.0667. The structure of the title compound, (C5H6N)7(BiCl6)2(NO3) consists of seven monoprotonated pyridinium (C5H6N)+ cations, two independent octahedron [BiCl6]3- and an isolated NO3- anion. These entities are linked together through N-H.....Cl and N-H.....O hydrogen bonds, originating from the (C5H6N)+ groups and the isolated anion of nitrate to forming a three dimensional network.

Three Dimensional Structure of UMo8O26: Ordering of U-Vacancies

2002 ◽  
Vol 718 ◽  
Author(s):  
N.D. Zakharov ◽  
P. Werner
Keyword(s):  
Low Temperatures ◽  
Driving Force ◽  
Three Dimensional ◽  
Solid State Reaction Method ◽  
Dimensional Structure ◽  
Unit Cell Parameters ◽  
Cell Parameters ◽  
Selected Area Electron Diffraction ◽  
Transmission Electron ◽  
Edx Microanalysis

AbstractThe structure and composition of UMo8O26 synthesized by solid state reaction method have been investigated by High Resolution Transmission Electron Microscopy (HRTEM), Selected Area Electron Diffraction, and EDX microanalysis. The ordering of U vacancies results in considerable enlargement of unit cell parameters: an=6.44 nm, bn=1.45 nm, cn=1.6 nm. It is build up of four layers piled up in c direction. Each following layer is shifted relative to previous one by vector bn/4. Eight hexagonal tunnels in each layer are filled by U atoms, while the eight others are vacant (V). Interaction between U cations and vacancies is driving force for ordering. The variation of stoichiometry can be a reason for appearance of incommensurate modulations in these crystals. It seems plausible that this structure might also exhibit superconductivity at low temperatures.

A Crystallographic Study of Bis[S-benzyl-5-bromo-2-oxoindolin-3-ylidenemethanehydrazonthioate] Disulfide Solvated with Dimethylsulfoxide

2012 ◽  
Vol 9 (2) ◽  
pp. 87
Author(s):  
Mohd Abdul Fatah Abdul Manan ◽  
M. Ibrahim M. Tahir ◽  
Karen A. Crouse ◽  
Fiona N.-F. How ◽  
David J. Watkin
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonds ◽  
Solvent Molecule ◽  
Site Occupancy ◽  
Unit Cell Parameters ◽  
Intermolecular Hydrogen Bonds ◽  
Triclinic Space Group ◽  
Cell Parameters ◽  
Crystallographic Study ◽  
Thiol Form

The crystal structure of the title compound has been determined. The compound crystallized in the triclinic space group P -1, Z = 2, V = 1839 .42( 18) A3 and unit cell parameters a= 11. 0460( 6) A, b = 13 .3180(7) A, c=13. 7321 (8) A, a = 80.659(3 )0, b = 69 .800(3 )0 and g = 77 .007 (2)0 with one disordered dimethylsulfoxide solvent molecule with the sulfur and oxygen atoms are distributed over two sites; S101/S102 [site occupancy factors: 0.6035/0.3965] and 0130/0131 [site occupancy factor 0.3965/0.6035]. The C22-S2 l and C 19-S20 bond distances of 1. 779(7) A and 1. 788(8) A indicate that both of the molecules are connected by the disulfide bond [S20-S21 2.055(2) A] in its thiol form. The crystal structure reveals that both of the 5-bromoisatin moieties are trans with respect to the [S21-S20 and CI 9-Nl 8] and [S20-S21 and C22-N23] bonds whereas the benzyl group from the dithiocarbazate are in the cis configuration with respect to [S21-S20 and C19-S44] and [S20-S21 and C22-S36] bonds. The crystal structure is further stabilized by intermolecular hydrogen bonds of N9-H35···O16 formed between the two molecules and N28-H281 ···O130, N28-H281 ···O131 and C4 l-H4 l l ···O 131 with the solvent molecule.

X-ray powder diffraction data of LaNi0.5Ti0.45Co0.05O3, LaNi0.45Co0.05Ti0.5O3, and LaNi0.5Ti0.5O3 perovskites

2021 ◽  
pp. 1-6
Author(s):  
Mariana M. V. M. Souza ◽  
Alex Maza ◽  
Pablo V. Tuza
Keyword(s):  
Crystal Structure ◽  
Rietveld Method ◽  
Pechini Method ◽  
Powder Diffraction Data ◽  
X Ray Diffraction ◽  
Unit Cell Parameters ◽  
X Ray ◽  
Cell Parameters ◽  
Modified Pechini Method ◽  
Scanning Electron

In the present work, LaNi0.5Ti0.45Co0.05O3, LaNi0.45Co0.05Ti0.5O3, and LaNi0.5Ti0.5O3 perovskites were synthesized by the modified Pechini method. These materials were characterized using X-ray fluorescence, scanning electron microscopy, and powder X-ray diffraction coupled to the Rietveld method. The crystal structure of these materials is orthorhombic, with space group Pbnm (No 62). The unit-cell parameters are a = 5.535(5) Å, b = 5.527(3) Å, c = 7.819(7) Å, V = 239.2(3) Å3, for the LaNi0.5Ti0.45Co0.05O3, a = 5.538(6) Å, b = 5.528(4) Å, c = 7.825(10) Å, V = 239.5(4) Å3, for the LaNi0.45Co0.05Ti0.5O3, and a = 5.540(2) Å, b = 5.5334(15) Å, c = 7.834(3) Å, V = 240.2(1) Å3, for the LaNi0.5Ti0.5O3.

scholarly journals Crystal Structure Refinements of Four Monazite Samples from Different Localities

Minerals ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1028 ◽  
Author(s):  
M. Mashrur Zaman ◽  
Sytle M. Antao
Keyword(s):  
Crystal Structure ◽  
Electron Probe ◽  
Unit Cell Volume ◽  
Unit Cell ◽  
X Ray Diffraction ◽  
Unit Cell Parameters ◽  
X Ray ◽  
Cell Parameters ◽  
Large Unit Cell ◽  
A Site

This study investigates the crystal chemistry of monazite (APO4, where A = Lanthanides = Ln, as well as Y, Th, U, Ca, and Pb) based on four samples from different localities using single-crystal X-ray diffraction and electron-probe microanalysis. The crystal structure of all four samples are well refined, as indicated by their refinement statistics. Relatively large unit-cell parameters (a = 6.7640(5), b = 6.9850(4), c = 6.4500(3) Å, β = 103.584(2)°, and V = 296.22(3) Å3) are obtained for a detrital monazite-Ce from Cox’s Bazar, Bangladesh. Sm-rich monazite from Gunnison County, Colorado, USA, has smaller unit-cell parameters (a = 6.7010(4), b = 6.9080(4), c = 6.4300(4) Å, β = 103.817(3)°, and V = 289.04(3) Å3). The a, b, and c unit-cell parameters vary linearly with the unit-cell volume, V. The change in the a parameter is large (0.2 Å) and is related to the type of cations occupying the A site. The average <A-O> distances vary linearly with V, whereas the average <P-O> distances are nearly constant because the PO4 group is a rigid tetrahedron.

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