PHASE COMPOSITION AND CRYSTAL STRUCTURE OF DURIAN (DURIO ZIBETHINUS) HUSK WASTE POWDER USING RIETVELD METHOD

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.

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Crystal structure of magnesium chromium vanadate Mg2CrV3O11, a member of the A2BV3O11 vanadate family

Powder Diffraction ◽

10.1154/1.2770746 ◽

2007 ◽

Vol 22 (3) ◽

pp. 246-252 ◽

Cited By ~ 4

Author(s):

A. Worsztynowicz ◽

S. M. Kaczmarek ◽

W. Paszkowicz ◽

R. Minikayev

Keyword(s):

Crystal Structure ◽

Rietveld Method ◽

Ion Pairs ◽

Exchange Constant ◽

Type I ◽

Type Ii ◽

Paramagnetic Resonance ◽

Interatomic Distances ◽

Electron Paramagnetic ◽

Full Occupancy

The crystal structure of recently discovered chromium (III) dimagnesium trivanadate (V) Mg2CrV3O11 was refined using the Rietveld method. The crystal system of Mg2CrV3O11 is triclinic with space group P1− (Mg1.7Zn0.3GaV3O11 type) and lattice parameters a=6.4057(1) Å, b=6.8111(1) Å, c=10.0640(2) Å, α=97.523(1)°, β=103.351(1)°, γ=101.750(1)°, and Z=2. The characteristic feature of compounds in the A2BV3O11 (A=Mg, Zn and B=Ga, Fe, Cr) family is a strong tendency to share the octahedral M(1) and M(2) sites by both divalent A and trivalent B atoms, and the bipyramidal M(3) sites occupied by divalent A ions. In the present refinement, the only constraint assuming full occupancy of the M(1), M(2), and M(3) sites leads to the following Cr/(Cr+Mg) ratios: 0.70(2) at M(1), 0.24(2) at M(2), and 0.03(2) at M(3). These occupancies are discussed and compared to those of isotypic compounds. The values of interatomic distances are found to be comparable with those reported by R. D. Shannon in 1976. Electron paramagnetic resonance has been also analyzed. Two absorption lines with g≈2.0 (type I) and g≈1.98 (type II) have been recorded in the EPR spectra, and attributed to V4+ ions and Cr3+–Cr3+ ion pairs, respectively. The exchange constant J between Cr3+ ions has been calculated.

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Crystal Structure Refinement of Gaivinoxyl Radical, C29H41O2, Based on Synchrotron X-ray Powder Diffraction and Rietveld Method

Journal of the Chinese Chemical Society ◽

10.1002/jccs.199400111 ◽

1994 ◽

Vol 41 (6) ◽

pp. 797-802 ◽

Cited By ~ 3

Author(s):

Hwo-Shuenn Sbeu ◽

Chih-Hao Lee ◽

Yu Wang ◽

Long Y. Chiang

Keyword(s):

Crystal Structure ◽

Powder Diffraction ◽

Rietveld Method ◽

Structure Refinement ◽

Crystal Structure Refinement ◽

X Ray

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Crystallographic study of ternary ordered skutterudite IrGe1.5Se1.5

Powder Diffraction ◽

10.1154/1.3478411 ◽

2010 ◽

Vol 25 (3) ◽

pp. 247-252 ◽

Cited By ~ 3

Author(s):

F. Laufek ◽

J. Návrátil

Keyword(s):

Crystal Structure ◽

Powder Diffraction ◽

Diffraction Data ◽

Rietveld Method ◽

Crystallographic Data ◽

Powder Diffraction Data ◽

X Ray ◽

Crystallographic Study ◽

Related Phase ◽

The Ideal

The crystal structure of skutterudite-related phase IrGe1.5Se1.5 has been refined by the Rietveld method from laboratory X-ray powder diffraction data. Refined crystallographic data for IrGe1.5Se1.5 are a=12.0890(2) Å, c=14.8796(3) Å, V=1883.23(6) Å3, space group R3 (No. 148), Z=24, and Dc=8.87 g/cm3. Its crystal structure can be derived from the ideal skutterudite structure (CoAs3), where Se and Ge atoms are ordered in layers perpendicular to the [111] direction of the original skutterudite cell. Weak distortions of the anion and cation sublattices were also observed.

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Quantitative Phase-Composition Analysis of Liquid-Phase-Sintered Silicon Carbide Using the Rietveld Method

Journal of the American Ceramic Society ◽

10.1111/j.1151-2916.2000.tb01548.x ◽

2004 ◽

Vol 83 (9) ◽

pp. 2282-2286 ◽

Cited By ~ 36

Author(s):

Angel L. Ortiz ◽

Francisco L. Cumbrera ◽

Florentino Sánchez-Bajo ◽

Fernando Guiberteau ◽

Huiwen Xu ◽

...

Keyword(s):

Silicon Carbide ◽

Phase Composition ◽

Liquid Phase ◽

Rietveld Method ◽

Composition Analysis ◽

Quantitative Phase ◽

Phase Composition Analysis ◽

Sintered Silicon

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Crystal structure of potassium tetraperoxomolybdate (VI) K2[Mo(O2)4]

Powder Diffraction ◽

10.1154/1.1997170 ◽

2005 ◽

Vol 20 (3) ◽

pp. 203-206 ◽

Cited By ~ 4

Author(s):

M. Grzywa ◽

M. Różycka ◽

W. Łasocha

Keyword(s):

Crystal Structure ◽

Low Temperature ◽

Diffraction Pattern ◽

Powder Diffraction ◽

Rietveld Method ◽

Structure Refinement ◽

Crystal Structure Refinement ◽

Unit Cell Parameters ◽

X Ray ◽

Cell Parameters

Potassium tetraperoxomolybdate (VI) K2[Mo(O2)4] was prepared, and its X-ray powder diffraction pattern was recorded at low temperature (258 K). The unit cell parameters were refined to a=10.7891(2) Å, α=64.925(3)°, space group R−3c (167), Z=6. The compound is isostructural with potassium tetraperoxotungstate (VI) K2[W(O2)4] (Stomberg, 1988). The sample of K2[Mo(O2)4] was characterized by analytical investigations, and the results of crystal structure refinement by Rietveld method are presented; final RP and RWP are 9.79% and 12.37%, respectively.

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Ba5(IO6)2: crystal structure evolution from room temperature to 80 K

Acta Crystallographica Section E Crystallographic Communications ◽

10.1107/s2056989021004990 ◽

2021 ◽

Vol 77 (6) ◽

pp. 634-637

Author(s):

David Wenhua Bi ◽

Priya Ranjan Baral ◽

Arnaud Magrez

Keyword(s):

Crystal Structure ◽

Room Temperature ◽

Structural Transition ◽

Rietveld Method ◽

Structural Parameters ◽

Structure Evolution ◽

X Ray Diffraction ◽

Lattice Contraction ◽

Interatomic Distances ◽

Crystallographic Axes

The crystal structure of Ba5(IO6)2, pentabarium bis(orthoperiodate), has been re-investigated at room temperature based on single-crystal X-ray diffraction data. In comparison with a previous crystal structure determination by the Rietveld method, an improved precision of the structural parameters was achieved. Additionally, low-temperature measurements allowed the crystal structure evolution to be studied down to 80 K. No evidence of structural transition was found even at the lowest temperature. Upon cooling, the lattice contraction is more pronounced along the b axis. This contraction is found to be inhomogeneous along different crystallographic axes. The interatomic distances between different Ba atoms reduce drastically with lowering temperature, resulting in a closer packing around the IO6 octahedra, which remain largely unaffected.

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Люминофоры холодного голубого излучения на основе оксида алюминия, допированного диспрозием

Физика твердого тела ◽

10.21883/ftt.2022.01.51837.196 ◽

2022 ◽

Vol 64 (1) ◽

pp. 95

Author(s):

И.В. Бакланова ◽

В.Н. Красильников ◽

А.П. Тютюнник ◽

Я.В. Бакланова

Keyword(s):

Crystal Structure ◽

Phase Composition ◽

Diffraction Analysis ◽

Powder Diffraction ◽

Thermal Quenching ◽

Emission Spectra ◽

X Ray ◽

White Emission ◽

Uv Excitation ◽

Quenching Of Luminescence

Al2О3:Dy3+ oxides with different colors luminescence were synthesized using precursor technology. The phase composition and crystal structure of the obtained materials were established by X-ray powder diffraction analysis. The excitation and emission spectra, decay curves, thermal quenching of luminescence were studied. Under UV excitation, the phosphors exhibit blue, purplish blue, white emission depending on the concentration of dysprosium and the temperature of annealing of the Al1-xDyx(OH)(HCOO)2 precursor in air.

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