Structure of AFeTi(PO4)3 (A=Ca,Cd) Nasicon phases from powder X-ray data

2004 ◽  
Vol 19 (2) ◽  
pp. 157-161 ◽  
Author(s):  
Abderrahim Aatiq ◽  
Hicham Dhoum
Keyword(s):  
Solid State ◽  
Diffraction Data ◽  
Solid State Reaction ◽  
Rietveld Analysis ◽  
Nasicon Structure ◽  
X Ray Diffraction ◽  
Hexagonal Cell ◽  
X Ray ◽  
Cell Parameters ◽  
Anion Distance

AFeTi(PO4)3 (A=Ca,Cd) materials were obtained by solid state reaction in air at 1000 °C. Structures of the two compounds were determined from X-ray diffraction data using Rietveld analysis. Both phases exhibit the Nasicon-type structure (R3¯c space group) with a statistical Fe(Ti) distribution within the framework. Their hexagonal cell parameters are a=8.518(1) Å, c=21.797(2) Å and a=8.534(1) Å, c=21.416(2) Å, for CaFeTi(PO4)3 and CdFeTi(PO4)3, respectively. Cd atoms occupy the M1 site in CdFeTi(PO4)3. From XRD data, it is difficult to distinguish without ambiguity between Ca2+ and Ti4+ ions in CaFeTi(PO4)3. Nevertheless from the cation–anion distance found after the structure determination, Ca2+ distribution within the M1 site of Nasicon structure are validated.

Crystal and Powder X-Ray Diffraction Data for TlBeXO4 (X = P, As)

1992 ◽  
Vol 7 (1) ◽  
pp. 44-46 ◽  
Author(s):  
G. Wallez ◽  
A. Elfakir ◽  
M. Quartern
Keyword(s):  
Solid State ◽  
Powder Diffraction ◽  
Diffraction Data ◽  
Solid State Reaction ◽  
Powder Diffraction Data ◽  
X Ray Diffraction ◽  
Unit Cell Parameters ◽  
X Ray ◽  
Cell Parameters ◽  
New Compounds

AbstractTwo new compounds TlBeXO4 (X = P, As) have been synthesized by solid state reaction. Single crystals were obtained. These compounds are isotypic, space group Pna21, Z = 4. Unit-cell parameters were determined. Powder diffraction data for each phase are reported.

Crystallochemistry and structural studies of two newly CaSb0.50Fe1.50(PO4)3 and Ca0.50SbFe(PO4)3 Nasicon phases

2006 ◽  
Vol 21 (1) ◽  
pp. 45-51 ◽  
Author(s):  
Abderrahim Aatiq ◽  
My Rachid Tigha ◽  
Rabia Hassine ◽  
Ismael Saadoune
Keyword(s):  
Solid State ◽  
Room Temperature ◽  
Rietveld Analysis ◽  
Structural Studies ◽  
Hexagonal Cell ◽  
Conventional Solid State Reaction ◽  
Space Group ◽  
X Ray ◽  
Cell Parameters ◽  
Crystallographic Structures

Crystallographic structures of two new orthophosphates Ca0.50SbFe(PO4)3 and CaSb0.50Fe1.50(PO4)3 obtained by conventional solid state reaction techniques at 900 °C, were determined at room temperature from X-ray powder diffraction using Rietveld analysis. The two compounds belong to the Nasicon structural family. The space group is R3 for Ca0.50SbFe(PO4)3 and R3c for CaSb0.50Fe1.50(PO4)3. Hexagonal cell parameters for Ca0.50SbFe(PO4)3 and CaSb0.50Fe1.50(PO4)3 are: a=8.257(1) Å, c=22.276(2) Å, and a=8.514(1) Å, c=21.871(2) Å, respectively. Ca2+ and vacancies in {[Ca0.50]3a[◻0.50]3b}M1SbFe(PO4)3 are ordered within the two positions, 3a and 3b, of M1 sites. Structure refinements show also a quasi-ordered distribution of Sb5+ and Fe3+ ions within the Nasicon framework. Thus, in {[Ca0.50]3a[◻0.50]3b}M1SbFe(PO4)3, each Ca(3a)O6 octahedron shares two faces with two Fe3+O6 octahedra and each vacancy (◻(3b)O6) site is located between two Sb5+O6 octahedra. In [Ca]M1Sb0.50Fe1.50(PO4)3 compound (R3c space group), all M1 sites are occupied by Ca2+ and the Sb5+ and Fe3+ ions are randomly distributed within the Nasicon framework.

Structure analysis of CaTi1−xSnxO3 (x = 0.0–1.0) solid solutions

2014 ◽  
Vol 29 (3) ◽  
pp. 254-259 ◽  
Author(s):  
Naoki Takani ◽  
Hisanori Yamane
Keyword(s):  
Solid State ◽  
Solid Solutions ◽  
Solid State Reaction ◽  
X Ray Diffraction ◽  
Unit Cell Parameters ◽  
X Ray ◽  
Cell Parameters ◽  
Diffraction Patterns ◽  
Perovskite Type ◽  
Perovskite Type Structure

CaTi1−xSnxO3 (x = 0.0–1.0) solid solutions were prepared by solid-state reaction at 1450 °C. Rietveld refinement of their powder X-ray diffraction patterns revealed that all the solid solutions crystallized in orthorhombic cells with the perovskite-type structure, the space group Pbnm. The refined unit-cell parameters linearly increased with nominal tin contents x.

scholarly journals RbCa2Nb3O10from X-ray powder data

2009 ◽  
Vol 65 (6) ◽  
pp. i44-i44 ◽  
Author(s):  
Zhen-Hua Liang ◽  
Kai-Bin Tang ◽  
Qian-Wang Chen ◽  
Hua-Gui Zheng
Keyword(s):  
Crystal Structure ◽  
Solid State ◽  
Powder Diffraction ◽  
Diffraction Data ◽  
Solid State Reaction ◽  
Perovskite Structure ◽  
Three Dimensional ◽  
Rietveld Analysis ◽  
Powder Diffraction Data ◽  
X Ray

Rubidium dicalcium triniobate(V), RbCa2Nb3O10, has been synthesized by solid-state reaction and its crystal structure refined from X-ray powder diffraction data using Rietveld analysis. The compound is a three-layer perovskite Dion–Jacobson phase with the perovskite-like slabs derived by termination of the three-dimensional CaNbO3perovskite structure along theabplane. The rubidium ions (4/mmmsymmetry) are located in the interstitial space.

Improved powder X-ray data for Cancrinites III: Davyne

1997 ◽  
Vol 12 (2) ◽  
pp. 99-102 ◽  
Author(s):  
Paolo Ballirano ◽  
Adriana Maras ◽  
Peter R. Buseck ◽  
Ann M. Yates
Keyword(s):  
Diffraction Data ◽  
Crystal Chemical ◽  
Angular Range ◽  
X Ray Diffraction ◽  
Hexagonal Cell ◽  
Space Group ◽  
X Ray ◽  
Cell Parameters

New powder X-ray diffraction data of davyne, a member of the cancrinite group of minerals, were collected using a rotating anode diffractometer: the hexagonal cell parameters are a=12.6711(3) Å, c=5.3278(2) Å, volume 740.82(4) Å3 (space group P63). The strongest lines are: 3.658(100), 4.790(73), 3.272(70), 2.112(48), 2.438(22), 2.663(19), 1.781(19), and 4.147(17). The new data provide quantitative intensities improved precision in d-spacings and cover an increased 2θ angular range with respect to PDF 20-379. Measured intensities and a simulated pattern are reported together with crystal-chemical considerations.

Powder X-ray data for adenosine C10H13N5O4

2000 ◽  
Vol 15 (2) ◽  
pp. 112-115 ◽  
Author(s):  
Ruggero Caminiti ◽  
Giancarlo Ortaggi ◽  
Raffaele Antonio Mazzei ◽  
Paolo Ballirano ◽  
Rita Rizzi
Keyword(s):  
Diffraction Data ◽  
Rietveld Analysis ◽  
Monoclinic Space Group ◽  
Angular Range ◽  
X Ray Diffraction ◽  
Space Group ◽  
X Ray ◽  
Cell Parameters ◽  
Better Than

New powder X-ray diffraction data of adenosine C10H13N5O4 were reported: cell parameters are a=4.8386(4) Å, b=10.2919(4) Å, c=11.8555(4) Å, β=99.298(5)°, volume 582.63(4)Å for the monoclinic space group P21. The strongest lines are: 7.723 (100), 5.085 (50), 5.851 (45), 4.710 (11), 3.881 (10), 3.899 (9), 3.292 (9), and 3.261 (9). Reported intensities are validated by Rietveld analysis. The data consist of measured positions and intensities and cover an angular range up to 75° 2θ and are significantly better than PDF 35-1977. Experimental, calculated, and difference patterns are also reported.

Crystal structure and X-ray diffraction data of a new hexagonal perovskite compound, Ba4CuNb3O12

2011 ◽  
Vol 26 (3) ◽  
pp. 244-247
Author(s):  
N. Kumada ◽  
W. Zhang ◽  
Q. Dong ◽  
T. Mochizuki ◽  
Y. Yonesaki ◽  
...  
Keyword(s):  
Crystal Structure ◽  
High Temperature ◽  
Chemical Composition ◽  
Solid State ◽  
Diffraction Data ◽  
Solid State Reaction ◽  
Inert Atmosphere ◽  
X Ray Diffraction ◽  
X Ray ◽  
Barium Copper

A new barium copper niobate, Ba4CuNb3O12, was successfully prepared by high-temperature solid-state reaction in an inert atmosphere. Rietveld-refinement analysis of the XRD data of the compound showed that it has the 8H-type hexagonal perovskite structure with space group P63/mmc (#194), a = 5.830(1) Å, c = 19.123(1) Å, and chemical composition of Ba4Cu1.84Nb2.16O12-δ.

Crystal and X-Ray Powder Data for Three Orthovanadates M Th2 (VO4)3 (M = K, Rb, Cs)

1989 ◽  
Vol 4 (3) ◽  
pp. 165-167 ◽  
Author(s):  
A. Elfakir ◽  
J.P. Souron ◽  
M. Quartern
Keyword(s):  
Solid State ◽  
Single Crystals ◽  
Powder Diffraction ◽  
Diffraction Data ◽  
Solid State Reaction ◽  
Monoclinic Space Group ◽  
Powder Diffraction Data ◽  
Unit Cell Parameters ◽  
X Ray ◽  
Cell Parameters

AbstractThree isotopic orthovanadates MTh2 (VO4)3 with M = K, Rb, Cs have been syndiesized by solid state reaction. Single crystals of K Th2 (VO4)3 and Rb Th2 (VO4)3 were obtained. These compounds are isotypic with the corresponding orthophosphates: monoclinic, space group C2/c, Z = 4. Unit-cell parameters for die diree compounds were determined. Powder diffraction data for each phase are reported.

Determination of Crystal Structure of Cd3(BO3)2 by Powder X-Ray Diffraction

1991 ◽  
Vol 6 (1) ◽  
pp. 28-30 ◽  
Author(s):  
Y. Laureiro ◽  
M.L. Veiga ◽  
M.L. López ◽  
S. García-Martín ◽  
A. Jerez ◽  
...  
Keyword(s):  
Crystal Structure ◽  
Solid State ◽  
Low Temperatures ◽  
Rietveld Analysis ◽  
Powder Diffraction Data ◽  
X Ray Diffraction ◽  
Orthorhombic System ◽  
X Ray ◽  
Cell Parameters

AbstractCd3(BO3)2 was prepared by a solid state reaction between B(OH)3 and Cd(OH)2 at low temperatures ranging between 523° and 623° and at a pressure of 10−4 – 10−5 Hg mm. The crystal structure has been refined by Rietveld analysis of X-ray powder diffraction data. The compound crystallizes in the orthorhombic system, space group Pnnm, Z = 2, with cell parameters of a = 5.967(5) Å, b = 4.78 (0) Å and c = 9.009(5) Å.

Structures of two newly synthesized A0.50SbFe(PO4)3 (A=Mn, Cd) Nasicon phases

2005 ◽  
Vol 20 (1) ◽  
pp. 33-39 ◽  
Author(s):  
Abderrahim Aatiq ◽  
Rabia Hassine ◽  
My Rachid Tigha ◽  
Ismael Saadoune
Keyword(s):  
Solid State ◽  
Powder Diffraction ◽  
Solid State Reaction ◽  
Cation Distribution ◽  
Room Temperature ◽  
Rietveld Method ◽  
Hexagonal Cell ◽  
X Ray ◽  
Cell Parameters ◽  
Two Samples

Crystal structures of A0.50SbFe(PO4)3(A=Mn, Cd) phases, obtained by solid state reaction at 920 °C, were determined at room temperature from X-ray powder diffraction (XRD) using the Rietveld method. The structures of the two samples are of the Nasicon-type with the R3 space group. Hexagonal cell parameters for A=Mn and Cd are: a=8.375(1) Å, c=21.597(2) Å and a=8.313(1) Å, c=21.996(2) Å, respectively. From XRD data, it is difficult to unambiguously distinguish between Cd2+ and Sb5+ ions in Cd0.50SbFe(PO4)3 and between Mn2+ and Fe3+ cations in Mn0.50SbFe(PO4)3. Nevertheless the overall set of cation–anion distances within the Nasicon framework clearly shows that the cation distribution can be illustrated by the {[A0.50]3a[◻0.50]3b}M1SbFe(PO4)3 (A=Mn, Cd) crystallographic formula. The divalent A2+ cations and vacancies are ordered within the two positions, 3a and 3b, of the M1 sites. Structure refinements show also a quasi-ordered distribution of Sb5+ and Fe3+ ions within the Nasicon framework. Thus, each A(3a)O6(A=Mn, Cd) octahedron shares two faces with two Fe3+O6 octahedra and each vacancy (◻(3b)O6) site is located between two Sb5+O6 octahedra.

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