scholarly journals The crystal chemistry and electrical properties of Fe doped Ca12Al14O33 (Mayenite)

2021 ◽  
Vol 40 (4) ◽  
pp. 591-597
Author(s):  
S.N. Ude ◽  
C.J. Rawn ◽  
T.T. Meek
Keyword(s):  
Solid State ◽  
Electrical Properties ◽  
Crystal Chemistry ◽  
Powder Diffraction ◽  
Synthesis Method ◽  
Neutron Powder Diffraction ◽  
Solid State Synthesis ◽  
Powder Diffraction Data ◽  
X Ray ◽  
Phase Pure

X-ray and neutron powder diffraction have been used to study the crystal chemistry of Fe doped mayenite (Ca12Al14-xFexO33). Solid- state synthesis was used to prepare Ca12Al14-xFexO33 where x = 0, 0.1, 0.2, 0.5 and 0.6 and the citrate gel route was used to prepare Ca12Al14-xFexO33 where x = 0, 0.05, 0.1, 0.2, 0.3 and 0.4. X-ray powder diffraction data indicate that samples with the same composition but synthesized by the citrate gel route were more likely to be phase pure than samples obtained by traditional solid-state synthesis. The refined lattice parameters were observed to increase with increasing Fe concentration, irrespective of the synthesis method. Refined neutron powder data confirm that Fe is going into Al site rather than Ca site. A 2-point probe was used to measure the electrical properties of the Fe doped citrate gel synthesized samples and showed that the resistivity increases for the Fe doped samples compared to the undoped mayenite.

scholarly journals Structural Chemistry of Some Phases in The YC-Ni-B System

1994 ◽  
Vol 376 ◽  
Author(s):  
B. C. Chakoumakos
Keyword(s):  
Powder Diffraction ◽  
Single Phase ◽  
Rietveld Analysis ◽  
Neutron Powder Diffraction ◽  
The Other ◽  
Powder Diffraction Data ◽  
X Ray ◽  
Neutron Powder Diffraction Data ◽  
Arc Melting ◽  
Phase Pure

ABSTRACTNiB, monoclinic Ni4B3, Ni2B and Ni3B were prepared by arc-melting and their roomtemperature crystal structures were refined by Rietveld analysis of neutron powder diffraction data. The NiB refinement is altogether new data. Although the B atoms in NiB form characteristic zigzag chains, the primary coordination of each atom by atoms of the other kind is similar and distinctively sevenfold, with one short (2.117 Å), two intermediate (2.152 Å), and four long (2.163 Å) bonds. Other samples with stoichiometries (YC)nNi2B2, n = 3, 4, did not yield single-phase material, but both x-ray and neutron powder diffraction suggest that the n = 4 structure is present in both of these samples. Phase-pure samples of these homologues may require non-stoichiometry and a more controlled thermal history than is attainable by arc melting.

scholarly journals Crystal structures of the triple perovskites Ba2K2Te2O9and Ba2KNaTe2O9, and redetermination of the double perovskite Ba2CaTeO6

2018 ◽  
Vol 74 (7) ◽  
pp. 1006-1009 ◽  
Author(s):  
Matthias Weil
Keyword(s):  
Solid State ◽  
Single Crystals ◽  
Powder Diffraction ◽  
Diffraction Data ◽  
Perovskite Structure ◽  
Double Perovskite ◽  
Powder Diffraction Data ◽  
Space Group ◽  
X Ray ◽  
Group Type

Single crystals of Ba2K2Te2O9(dibarium dipotassium nonaoxidoditellurate), (I), Ba2KNaTe2O9(dibarium potassium sodium nonaoxidoditellurate), (II), and Ba2CaTeO6(dibarium calcium hexaoxidotellurate), (III), were obtained from KNO3/KI or KNO3/NaNO3flux syntheses in platinum crucibles for (I) and (II), or porcelain crucibles for (III). (I) and (II) are isotypic and are members of triple perovskites with general formulaA2[12co]A′[12co]B2[6o]B′[6o]O9. They crystallize in the 6H-BaTiO3structure family in space-group typeP63/mmc, with theA,A′,BandB′ sites being occupied by K, Ba, Te and a second Ba in (I), and in (II) by mixed-occupied (Ba/K), Ba, Te and Na sites, respectively. (III) adopts theA2[12co]B′[6o]B′′[6o]O6double perovskite structure in space-group typeFm-3m, with Ba, Ca and Te located on theA,B′ andB′′sites, respectively. The current refinement of (III) is based on single-crystal X-ray data. It confirms the previous refinement from X-ray powder diffraction data [Fuet al.(2008).J. Solid State Chem.181, 2523–2529], but with higher precision.

BaCeN2, ein Bariumnitridocerat(IV) mit einer Struktur vom anti-TiP-Typ / BaCeN2, a Bariumnitridocerate(IV ) with a Structure of the anti-TiP Type

1994 ◽  
Vol 49 (9) ◽  
pp. 1169-1174 ◽  
Author(s):  
Oliver Seeger ◽  
Joachim Strähle
Keyword(s):  
Powder Diffraction ◽  
Diffraction Data ◽  
Neutron Powder Diffraction ◽  
Type Structure ◽  
Stoichiometric Ratio ◽  
Powder Diffraction Data ◽  
X Ray ◽  
Neutron Powder Diffraction Data ◽  
Moisture Sensitive ◽  
Trigonal Prismatic

Reaction of Ba3N2 with CeN in the stoichiometric ratio 1:3 at 850 °C under an atmosphere of N2 followed by quenching yields air and moisture sensitive BaCeN2. The product crystallizes isotypically to β-RbScO2 with the anti-TiP type structure in the hexagonal space group P63/mmc with a = 365.06(2), c = 1266.03(3) pm, Z = 2. The structure was determined using X-ray and neutron powder diffraction data. In the structure the Ba2+ cations occupy trigonal prismatic holes with distances Ba-N = 288(1) pm while the Ce atoms are in octahedral positions with distances C e -N = 242.4(8) pm

Powder-diffraction data for several solid solutions with the compositions (CaxSr1−x)CuO2 and (CaxSr1−x)2CuO3

1995 ◽  
Vol 10 (4) ◽  
pp. 296-299 ◽  
Author(s):  
S. T. Misture ◽  
C. Park ◽  
R. L. Snyder ◽  
B. Jobst ◽  
B. Seebacher
Keyword(s):  
High Temperature ◽  
Solid State ◽  
Powder Diffraction ◽  
Solid Solutions ◽  
Diffraction Data ◽  
Solid State Reaction ◽  
High Temperature Superconductors ◽  
Powder Diffraction Data ◽  
X Ray ◽  
Diffraction Patterns

Several compositions of the solid solutions (CaxSr1−x)CuO2 and (CaxSr1−x)2CuO3, both of which are found as minor phases in the high-temperature superconductors, were prepared by solid-state reaction. X-ray powder-diffraction patterns for three compositions of (CaxSr1−x)CuO2 and two for (CaxSr1−x)2CuO3 are presented.

X-ray powder diffraction data of A-formula lanthanum and titanium substituted lead zirconate

2003 ◽  
Vol 18 (3) ◽  
pp. 252-262 ◽  
Author(s):  
Else Breval ◽  
Nichole Wonderling ◽  
Joseph P. Dougherty
Keyword(s):  
Powder Diffraction ◽  
Diffraction Data ◽  
Tetragonal Phase ◽  
Hexagonal Phase ◽  
Lead Zirconate ◽  
Powder Diffraction Data ◽  
X Ray Diffraction ◽  
X Ray ◽  
Phase Pure

PLZT of the compositions 0≤L≤12, and 0≤T≤10 was studied in order to describe the structure of the phases as a function of composition. This range contains a mixed region with PLZT+La2Zr2O7, an orthorhombic, a rhombohedral (hexagonal) phase, a tetragonal phase, and a mixture of different PLZT phases. Each phase pure composition is described by X-ray diffraction.

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.

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