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 of a new CaII1/3SbV1/6BiIII1/2PO4 phosphate

2013 ◽  
Vol 29 (1) ◽  
pp. 14-19 ◽  
Author(s):  
Abderrahim Aatiq ◽  
My Rachid Tigha
Keyword(s):  
Room Temperature ◽  
Structural Information ◽  
Rietveld Analysis ◽  
Infrared Spectroscopic Study ◽  
Conventional Solid State Reaction ◽  
Monoclinic System ◽  
X Ray ◽  
Cell Parameters ◽  
Air Atmosphere ◽  
Crystallographic Structures

A new Ca1/3Sb1/6Bi1/2PO4 “CaSb0.50Bi1.50(PO4)3” phosphate has been synthesized by conventional solid-state reaction techniques at 900 °C in air atmosphere. Their crystallographic structures were determined at room temperature from X-ray powder diffraction (XRPD) data using the Rietveld analysis. CaII1/3SbV1/6BiIII1/2PO4 material possesses the high-temperature BiPO4 monoclinic structure variety. It crystallizes in monoclinic system with P21/m space group and the cell parameters are: a = 4.9358(1) Å, b = 6.9953(2), c = 4.7075(1) Å, and β = 96.2(1)°. Their structure can be described as composed of alternating edge-sharing AO8 (A = Ca, Sb, Bi) bisdisphenoids and PO4 tetrahedra forming chains parallel to the b axis. Every AO8 polyhedron is surrounded by six PO4 and every PO4 tetrahedron is surrounded by six AO8 polyhedra. Infrared spectroscopic study was used to obtain further structural information.

Crystal structures of newly synthesized SbV1.50FeIII0.50(PO4)3 and (SbV0.50FeIII0.50)P2O7

2007 ◽  
Vol 22 (1) ◽  
pp. 47-54 ◽  
Author(s):  
Abderrahim Aatiq ◽  
Rachid Bakri
Keyword(s):  
Crystal Structure ◽  
Solid State ◽  
Powder Diffraction ◽  
Room Temperature ◽  
Rietveld Method ◽  
Hexagonal Cell ◽  
Space Group ◽  
X Ray ◽  
Cell Parameters ◽  
Air Atmosphere

Synthesis and structure of two phosphates belonging to the ternary Sb2O5-Fe2O3-P2O5 system are reported. Structures of both SbV1.50FeIII0.50(PO4)3 and (SbV0.50FeIIIe0.50)P2O7 phases, obtained by solid state reaction in air atmosphere at 950 °C and 900 °C, respectively, were determined at room temperature from X-ray powder diffraction using the Rietveld method. Sb1.50Fe0.50(PO4)3 phosphate belongs to the Nasicon-type structure with R32 space group. Hexagonal cell parameters are ahex.=8.305(1) Å and chex.=22.035(2) Å. Rietveld refinement results show a 2-2 ordered distribution, along the c-axis, of X(1) and X(2) sites (crystallographic formula [Sb0.88Fe0.12]X(1)[Fe0.38Sb0.62]X(2)(PO4)3) in the Nasicon framework. (Sb0.50Fe0.50)P2O7 is isotypic with β-SbP2O7 pyrophosphate [Pna21 space group; a=7.865(1) Å, b=15.699(2) Å, c=7.847(1) Å]. Its crystal structure is built up from corner-shared SbO6 or FeO6 octahedra and P2O7 groups (two group types). Each P2O7 group shares its six vertices with three SbO6 and three FeO6 octahedra, and each octahedra is connected to six P2O7 groups. A quasi 1-1 ordered distribution, along the b-axis, of Sb5+ and Fe3+ ions in the pyrophosphate framework are observed.

Structural characterization of two K2SnX(PO4)3 (X=Fe,Yb) with langbeinite structure

2006 ◽  
Vol 21 (3) ◽  
pp. 214-219 ◽  
Author(s):  
Abderrahim Aatiq ◽  
Btissame Haggouch ◽  
Rachid Bakri ◽  
Youssef Lakhdar ◽  
Ismael Saadoune
Keyword(s):  
Solid State ◽  
Powder Diffraction ◽  
Room Temperature ◽  
Cell Parameter ◽  
Rietveld Analysis ◽  
Conventional Solid State Reaction ◽  
X Ray ◽  
Octahedral Sites ◽  
Parameter Values

Structures of two K2SnX(PO4)3(X=Fe,Yb) phosphates, obtained by conventional solid state reaction techniques at 950 °C, were determined at room temperature by X-ray powder diffraction using Rietveld analysis. The two materials exhibit the langbeinite-type structure (P213 space group, Z=4). Cubic unit cell parameter values are: a=9.9217(4) Å and a=10.1583(4) Å for K2SnFe(PO4)3 and K2SnYb(PO4)3, respectively. Structural refinements show that the two crystallographically independent octahedral sites (of symmetry 3) have a mixed Sn∕X (X=Fe,Yb) population although ordering is stronger in the Yb phase than in the Fe phase.

Synthesis and structural characterization of ASnFe(PO4)3 (A=Na2,Ca,Cd) phosphates with the Nasicon type structure

2004 ◽  
Vol 19 (3) ◽  
pp. 272-279 ◽  
Author(s):  
Abderrahim Aatiq
Keyword(s):  
Room Temperature ◽  
Random Distribution ◽  
Rietveld Analysis ◽  
Type Structure ◽  
Conventional Solid State Reaction ◽  
X Ray ◽  
Cell Parameters ◽  
Nasicon Type ◽  
Cationic Distribution

The crystal structures of ASnFe(PO4)3 (A=Na2, Ca, Cd) phases, obtained by conventional solid state reaction techniques at (950–1000 °C), were determined at room temperature from X-ray powder diffraction (XRD) using Rietveld analysis. The three materials exhibit the Nasicon-type structure (R3c space group, Z=6) with a random distribution of Sn(Fe) within the framework. Hexagonal cell parameters when A=Na2, Ca and Cd are: a=8.628(1) Å, c=22.151(2) Å; a=8.569(1) Å, c=22.037(2) Å and a=8.587(1) Å, c=21.653(2) Å, respectively. Structural refinements show a partial occupancy of M1 (Na(1)) and M2 (Na(2)) sites in Na2SnFe(PO4)3 leading to the cationic distribution [Na1.22□1.78]M2[Na0.78□0.22]M1SnFe(PO4)3. Ca2+ ions are distributed only in the M1 site of [□3]M2[Ca]M1SnFe(PO4)3. From XRD data, it is difficult to unambiguously distinguish between Cd2+ and Sn4+ ions in CdSnFe(PO4)3. Nevertheless the overall set of cation–anion distances within the Nasicon framework clearly shows that the cationic distribution can be illustrated by the [□3]M2[Cd]M1SnFe(PO4)3 crystallographic formula. Distortion within the [Sn(Fe)(PO4)3] frameworks, in ASnFe(PO4)3 (A=Na2,Ca,Cd) phases, is shown to be related to the M1 site size. © 2004 International Centre for Diffraction Data.

Preparation and crystal structure of SbV1.50InIII0.50(PO4)3 and (SbV0.50InIII0.50)P2O7

2008 ◽  
Vol 23 (3) ◽  
pp. 232-240
Author(s):  
Abderrahim Aatiq ◽  
Rachid Bakri ◽  
Aaron Richard Sakulich
Keyword(s):  
Crystal Structure ◽  
Solid State ◽  
Room Temperature ◽  
Rietveld Method ◽  
Monoclinic Space Group ◽  
Unit Cell Parameters ◽  
Orthorhombic System ◽  
Space Group ◽  
X Ray ◽  
Cell Parameters

Synthesis and structure of two phosphates belonging to the ternary Sb2O5–In2O3–P2O5 system are realized. Structures of SbV1.50InIII0.50(PO4)3 and (SbV0.50InIII0.50)P2O7 phases, obtained by solid state reaction in air at 950 °C, were determined at room temperature from X-ray powder diffraction using the Rietveld method. SbV1.50InIII0.50(PO4)3 have a monoclinic (space group P21/n) distortion of the Sc2(W O4)3-type framework. Its structure is constituted by corner-shared SbO6 or InO6 octahedra and PO4 tetrahedra. Monoclinic unit cell parameters are a=11.801(2) Å, b=8.623(1) Å, c=8.372(1) Å, and β=90.93(1)°. (Sb0.50In0.50)P2O7 is isotypic with (Sb0.50Fe0.50)P2O7 and crystallizes in orthorhombic system (space group Pna21) with a=7.9389(1) Å, b=16.0664(2) Å, and c=7.9777(1) Å. Its structure is built up from corner-shared SbO6 or InO6 octahedra and P2O7 groups (two group-types). Each P2O7 group shares its six vertices with three SbO6 and three InO6 octahedra, and each octahedron is connected to six P2O7 groups.

scholarly journals Structure, Infrared and Raman spectroscopic studies of new AII(SbV0.50CrIII0.50)(PO4)2 (A = Ba, Sr, Pb) yavapaiite phases

2020 ◽  
Vol 10 (8) ◽  
pp. 734
Author(s):  
Hajar Bellefqih ◽  
Rachid Fakhreddine ◽  
Rachid Tigha ◽  
Abderrahim Aatiq
Keyword(s):  
Diffraction Method ◽  
Rietveld Analysis ◽  
Spectroscopic Studies ◽  
Conventional Solid State Reaction ◽  
Space Group ◽  
X Ray ◽  
Cell Parameters ◽  
Raman Spectroscopic ◽  
Air Atmosphere ◽  
Monoclinic Cell

<p class="Mabstract">Three new A<sup>II</sup>(Sb<sub>0.5</sub>Cr<sub>0.5</sub>)(PO<sub>4</sub>)<sub>2</sub> (A<sup>II</sup> = Ba, Sr, Pb) yavapaiite phases, abbreviated as [ASbCr], have been successfully synthesized by a conventional solid-state reaction in air atmosphere. Their crystal structures have been investigated by Rietveld analysis from the X-ray powder diffraction method. Results show that Ba(Sb<sub>0.5</sub>Cr<sub>0.5</sub>)(PO<sub>4</sub>)<sub>2</sub> crystallizes in monoclinic <em>C</em>2<em>/m</em> space group (Z = 2) with cell parameters a = 8.140(1) Å; b = 5.175(1) Å; c = 7.802(1) Å and β = 94.387(1)°. Structures of A<sup>II</sup>(Sb<sub>0.5</sub>Cr<sub>0.5</sub>)(PO<sub>4</sub>)<sub>2</sub> (A<sup>II </sup>= Sr, Pb) compounds are comparable, and both crystallize in a distorted yavapaiite structure with <em>C</em>2<em>/c</em> space group (Z = 4). Obtained monoclinic cell parameters are: a = 16.5038(2) Å; b = 5.1632(1) Å; c = 8.0410(1) Å; β = 115.85(1) for [SrSbCr] and a = 16.684(2) Å; b = 5.156(1) Å c = 8.115(1) Å; β = 115.35(1)° for [PbSbCr]. Infrared and Raman spectroscopic study was undertaken to provide information about vibrations bonds within the studied yavapaiite materials.</p>

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.

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.

Structural and spectroscopic study of NaSbR(PO4)3 (R = Cr, Fe, In) phases

2013 ◽  
Vol 28 (S2) ◽  
pp. S394-S408
Author(s):  
Abderrahim Aatiq ◽  
My Rachid Tigha
Keyword(s):  
Spectroscopic Study ◽  
Powder Diffraction ◽  
Room Temperature ◽  
Structural Information ◽  
Rietveld Analysis ◽  
Infrared Spectroscopic Study ◽  
Space Group ◽  
X Ray ◽  
Structural Family ◽  
Crystallographic Structures

Crystallographic structures of the three NaSbR(PO4)3 (R = Cr, Fe, In) phases were determined at room temperature from X-ray powder diffraction (XRD) data using the Rietveld analysis. The three compounds belong to the Nasicon structural family. The presence of the (303) reflection in all XRD spectra of NaSbR(PO4)3 shows clearly that all compounds crystallise in rhombohedral system with R3 space group. Na atoms are practically ordered within the two positions, 3a and 3b, of M1 sites. Structure refinements show also a partially-ordered distribution of Sb5+ and R3+ ions within the Nasicon framework. A Raman and Infrared spectroscopic study was used to obtain further structural information about the nature of bonding in NaSbR(PO4)3 (R = Cr, Fe, In) phases.

Crystal structure of Ca2Zn2(V4O14) and Pb2Cd2(V3O10)(VO4) double vanadates

2018 ◽  
Vol 33 (3) ◽  
pp. 216-224 ◽  
Author(s):  
V. D. Zhuravlev ◽  
A. P. Tyutyunnik ◽  
A. Y. Chufarov ◽  
N. I. Lobachevskaya ◽  
A. A. Velikodnyi
Keyword(s):  
Crystal Structure ◽  
Unit Cell ◽  
Powder Diffraction Data ◽  
Structural Refinement ◽  
Unit Cell Parameters ◽  
Monoclinic Symmetry ◽  
Conventional Solid State Reaction ◽  
Space Group ◽  
X Ray ◽  
Cell Parameters

Polycrystalline samples of Ca2Zn2(V4O14) (I) and Pb2Cd2(V3O10)(VO4) (II) were synthesized using the nitrate–citrate method (I) and conventional solid state reaction (II). The structural refinement based on X-ray powder diffraction data showed that the crystal structure of (I) is characterized by monoclinic symmetry with unit-cell parameters a = 6.8044(1) Å, b = 14.4876(3) Å, c = 11.2367(2) Å, β = 99.647(1)° [space group P21/c (No. 14), Z = 4], and the crystal structure of (II) is triclinic with unit-cell parameters a = 7.03813(6) Å, b = 12.9085(1) Å, c = 6.99961(5) Å, α = 90.7265(5)°, β = 96.3789(5)°, γ = 94.9530(6)°, V = 629.470(8) Å3 [space group P$\bar 1$ (No. 2), Z = 2].

Sign in / Sign up

Export Citation Format

Share Document