Structures and isomerization in diamminedichloropalladium(II)

1996 ◽  
Vol 52 (6) ◽  
pp. 909-916 ◽  
Author(s):  
S. D. Kirik ◽  
L. A. Solovyov ◽  
A. I. Blokhin ◽  
I. S. Yakimov ◽  
M. L. Blokhina
Keyword(s):  
Phase Transitions ◽  
Solid State ◽  
Powder Diffraction ◽  
Single Phase ◽  
Layer Structure ◽  
Powder Materials ◽  
Space Group ◽  
X Ray ◽  
Column Structure ◽  
Structure Determinations

Three forms (cis-, trans-, β-trans-) of [Pd(NH3)2Cl2] were obtained as pure single-phase powder materials. Ab initio structure determinations using X-ray powder diffraction were carried out. The cis-Pd(NH3)2Cl2 [a = 6.3121 (2), b = 6.4984 (2), c = 3.3886 (1) Å, α = 96.604 (4), β = 97.290 (4), γ = 104.691 (2)°, Z = 1, space group P1] and trans-Pd(NH3)2Cl2 [a = 6.5398 (3), b = 6.8571 (4), c = 6.3573 (3) Å, α = 103.311 (5), β = 102.454 (3), γ = 100.609 (4)°, Z = 2, space group P{\bar 1}] phases have a typical layer-column structure, while β-trans-Pd(NH3)2Cl2 [a = 8.1540 (2), b = 8.1482 (2), c = 7.7945 (1) Å, Z = 4, space group Pbca] is described as a parquet-like layer structure. Both trans phases demonstrate the order-disorder phenomenon. The possible ways of phase transitions are discussed. It is noted that the cis phase can transform into trans in the solid state without destroying the crystal body. Further transformation to β-trans follows through a break up of the crystal body.

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.

scholarly journals Solid State Transitions in Alkali Alkanoates: Diffractometric and Conductometric Measurements on Lithium, Sodium and Potassium Propanoates

1979 ◽  
Vol 34 (5) ◽  
pp. 575-578 ◽  
Author(s):  
A. Cingolani ◽  
G. Spinolo ◽  
M. Sanesi
Keyword(s):  
Phase Transitions ◽  
Solid State ◽  
Temperature Dependence ◽  
Powder Diffraction ◽  
State Transitions ◽  
Potassium Salts ◽  
Crystalline Phases ◽  
X Ray ◽  
Temperature Ranges ◽  
Sodium And Potassium

Abstract Conductometric measurements on solid lithium, sodium and potassium propanoates and X-ray powder diffraction measurements on the sodium and potassium salts have been performed over temperature ranges including solid state transitions. The temperature dependence of the transport and lattice parameters of the different crystalline phases and the changes of the same parameters in correspondence with phase transitions have been put into evidence.

Effect of Isovalent Substitution on the Formation and Luminescence Properties of Solid Solutions BiPXV1-XO4 Doped with Europium (III)

2015 ◽  
Vol 230 ◽  
pp. 62-66 ◽  
Author(s):  
Konstantin L. Bychkov ◽  
Katerina V. Terebilenko ◽  
Rostyslav P. Linnik ◽  
Nikolay S. Slobodyanik
Keyword(s):  
Solid Solution ◽  
Solid State ◽  
Luminescence Spectrum ◽  
Powder Diffraction ◽  
Solid Solutions ◽  
Single Phase ◽  
Photoluminescence Spectroscopy ◽  
Electronic Transitions ◽  
X Ray ◽  
Isovalent Substitution

Solid solution BiP0.9V0.1O4 from BiPXV1-XO4 system has been synthesized by solid state synthesis at 973 K. It has been shown that the phosphate-vanadate can be prepared as a single phase for x =0.9, while higher degree of (P/V)O4 substitution in BiVO4 has not been detected for the range studied. The substitution peculiarities have been investigated by X-Ray powder diffraction, infrared and photoluminescence spectroscopy. The luminescence spectrum of BiPXV1-XO4:Eu3+ solid solution reveal intensive photoluminescence lines related to f-f electronic transitions in Eu3+ ions.

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.

Synthesis, Structures and Spectroscopic Properties of 1 : 1 Complexes of Gold(I) Halides with Trimesitylphosphine

2000 ◽  
Vol 53 (3) ◽  
pp. 175 ◽  
Author(s):  
Raymond C. Bott ◽  
Graham A. Bowmaker ◽  
Robbie W. Buckley ◽  
Peter C. Healy ◽  
M. C. Senake Perera
Keyword(s):  
Infrared Spectroscopy ◽  
Solid State ◽  
Far Infrared ◽  
Spectroscopic Properties ◽  
Far Infrared Spectroscopy ◽  
Space Group ◽  
X Ray ◽  
Bond Lengths ◽  
Structure Determinations ◽  
Far Infrared Spectra

Monomeric two-coordinate gold(I) complexes, [Au(P(mes)3)X] (P(mes)3 = tris(2,4,6-trimethylphenyl)phosphine, X = Cl, Br and I), have been prepared and characterized by single-crystal X-ray structure determinations, far-infrared spectroscopy and solution and solid-state CPMAS 31 P n.m.r. spectroscopy. X-Ray structure determinations show that crystals obtained from solutions of [NBu4] [AuX2] and P(mes)3 in acetonitrile for X = Cl, Br and I and in dimethylformamide (dmf) for X = Br and I form an isomorphous series of complexes, crystallizing in space group P21/c with a ª 8, b ª 22, c ª 13 Å, b ª 98˚ (a form). Crystallization of the chloride from dimethylformamide yields the solvated complex [Au(P(mes)3)X]·(dmf) in space group P2/a with a 15.224(2), b 10.070(1), c 18.210(4) Å, b 100.42(2)˚. Electrochemical synthesis of the complexes for X = Cl and Br yield two new crystalline phases; the chloride in space group P21/c with a 10.249(2), b 8.189(2), c 31.844(3) Å, b 91.68(1)˚ (b form) and the bromide in space group Pbca with a 19.208(4), b 15.586(3), c 16.962(4) Å ( g form). The Au–P bond lengths increase in the order Cl < Br < I with distances c. 0.02–0.03 Å longer than average values for other [Au(PR3)X] complexes, reflecting steric congestion by the P(mes)3 ligand. For the unsolvated complexes, the Au–X distances are c. 0.02 Å shorter than average values. For the Cl/dmf solvate, both Au–P and Au–X bond lengths increase. For the a complexes, far-infrared spectra show n(Au 35,37 Cl) 336, 329 cm –1 , n(AuBr) 234 cm –1 and n(AuI) 195 cm –1 and solid-state 31 P CPMAS n.m.r. spectra yield broad peaks with d–3.9 (Cl), –0.6 (Br) and +6.0 I). For the Cl/dmf solvate, n(Au 35,37 Cl) are 334, 327 cm –1 and d is –4.4. Solution 31 P n.m.r. spectra in CDCl3 give sharp single peaks at d –5.0 (Cl), –1.4 (Br) and +5.5 (I) with the similarity of the values with those for the solid-state spectra consistent with similar conformational structures for the [Au(P(mes)3)X] molecules in the two states.

Structures of [Pd(NH3)2 X 2] and its chemical transformation in the solid state

2000 ◽  
Vol 56 (3) ◽  
pp. 419-425 ◽  
Author(s):  
S. D. Kirik ◽  
L. A. Solovyov ◽  
A. I. Blokhin ◽  
I. S. Yakimov
Keyword(s):  
Solid State ◽  
Powder Diffraction ◽  
Molecular Structures ◽  
Structural Determination ◽  
Powder Diffraction Data ◽  
Thermal Transformations ◽  
State Transformation ◽  
Solid State Transformation ◽  
Space Group ◽  
X Ray

Crystal structures of [Pd(NH3)2 X 2] complexes, where X = Br or I, diamminediiodo-/-dibromopalladium(II), have been studied by X-ray powder diffraction. The series consists of five complexes: cis-[Pd(NH3)2Br2] (I) [a = 13.3202 (7), b = 12.7223 (6), c = 7.05854 (3) Å, Z = 8, space group Pbca], trans-[Pd(NH3)2Br2] (II) [a = 6.7854 (3), b = 7.1057 (3), c = 6.6241 (2) Å, α = 103.221 (3), β = 102.514 (2), γ = 100.386 (3)°, Z = 2, space group P\overline 1], β-trans-[Pd(NH3)2Br2] (III) [a = 8.4315 (3), b = 8.4206 (3), c = 8.0916 (2) Å, Z = 4, space group Pbca], cis-[Pd(NH3)2I2] (IV) [a = 13.9060 (8), b = 13.5035 (8), c = 7.5050 (4) Å, Z = 8, space group Pbca], and β-trans-[Pd(NH3)2I2] (V) [a = 8.8347 (5), b = 8.8410 (5), c = 8.6081 (2) Å, Z = 4, space group Pbca]. Patterson synthesis and Rietveld refinement have been used for structural determination. Molecular structures with column- or parquet-type packing of flat complexes are characteristic of these substances. Corresponding cis- and β-trans compounds are isostructural. The thermal transformations cis→trans→β-trans (cis→β-trans in the case of iodine) are considered. Cl derivatives are also discussed. The transformations proceed irreversibly and are accompanied by decreasing specific volume. Owing to these features, they can be classified as chemical reactions. High-temperature X-ray powder diffraction was used to study the transformations in air. The set of data is consistent with a solid state transformation from cis to trans. According to this model, the columns of molecules remain intact during the process, and the transformation proceeds via the breaking of Pd...X and Pd...N intermolecular bonds. The powder diffraction data have been deposited in ICDD-JCPDS (45-0596, 46-0876, 46-0879, 47-1690, 48-1185).

Synthesis and Impedance Spectroscope of B-Doped La9.33+x/3(SiO4)6-x(BO4)xO2 Apatite Oxide Ion Conductor

2017 ◽  
Vol 904 ◽  
pp. 102-106
Author(s):  
Zhao Xiang Huang ◽  
Kan Yu ◽  
Jun Liang ◽  
Xiao Li Sheng
Keyword(s):  
Solid State ◽  
Powder Diffraction ◽  
Single Phase ◽  
Apatite Structure ◽  
Ion Conductor ◽  
X Ray ◽  
Oxide Ion Conductor ◽  
Conductivity Enhancement ◽  
Oxide Ion

B2O3 was doped into the oxide ion conductor La9.33(SiO4)6O2 according to the formula La9.33+x/3(SiO4)6-x(BO4)xO2 where 0 ≤ x ≤ 2. Samples were prepared by solid state reaction; difficulty was experienced in obtaining fully homogenised products at intermediate x, although they were nominally single-phase by X-ray powder diffraction. A small conductivity enhancement was observed at intermediate B content which further illustrates the important role of La vacancies in optimising the conductivity of La silicates with the apatite structure.

Metastable β-phase of benzophenone: independent structure determinations via X-ray powder diffraction and single crystal studies

2000 ◽  
Vol 56 (3) ◽  
pp. 486-496 ◽  
Author(s):  
Hartmut Kutzke ◽  
Helmut Klapper ◽  
Robert B. Hammond ◽  
Kevin J. Roberts
Keyword(s):  
Single Crystal ◽  
Powder Diffraction ◽  
Diffraction Data ◽  
Metastable Phase ◽  
Search Space ◽  
Powder Diffraction Data ◽  
Space Group ◽  
X Ray ◽  
Β Phase ◽  
Structure Determinations

Benzophenone was the first organic molecular material to be identified as polymorphic. It is well known that benzophenone crystallizes in a stable orthorhombic α-form (m.p. 321 K) with space group P212121 and a = 10.28, b = 12.12, c = 7.99 Å, [Girdwood (1998). Ph.D. thesis. Strathclyde University, Glasgow, Scotland]. Here we report two separate structure determinations of the metastable β-form (m.p. 297–299 K). Crystalline material of the metastable polymorph was obtained from a melt supercooled to ∼243 K. The structure was determined from X-ray powder diffraction data by employing a novel, computational systematic search procedure to identify trial packing arrangements for subsequent refinement. Unit-cell and space-group information, determined from indexing the powder diffraction data, was used to define the search space. The structure was also determined from single-crystal diffraction data at room temperature and at 223 K. The metastable phase is monoclinic with space group C2/c and a = 16.22, b = 8.15, c = 16.33 Å, β = 112.91° (at 223 K). The structures derived from the individual techniques are qualitatively the same. They are compared both with each other and with the stable polymorph and other benzophenone derivatives.

scholarly journals Rietveld refinement of the low temperature crystal structures of Cs2XSi5O12 (X = Cu, Cd and Zn)

2021 ◽  
Vol 12 (1) ◽  
pp. 60-63
Author(s):  
Anthony Martin Thomas Bell
Keyword(s):  
High Temperature ◽  
Solid State ◽  
Low Temperature ◽  
Rietveld Refinement ◽  
Powder Diffraction ◽  
Low Temperatures ◽  
Powder Diffraction Data ◽  
Space Group ◽  
X Ray ◽  
Silicate Framework

The synthetic leucite silicate framework mineral analogues Cs2XSi5O12 (X = Cu, Cd, Zn) were prepared by high-temperature solid-state synthesis. The results of Rietveld refinement, using 18 keV synchrotron X-ray powder diffraction data collected at low temperatures (8K X = Cu, Zn; 10K X = Cd) show that the title compounds crystallize in the space group Pbca and are isostructural with the ambient temperature structures of these analogues. The structures consist of tetrahedrally coordinated SiO4 and XO4 sharing corners to form a partially substituted silicate framework. Extraframework Cs cations sit in channels in the framework. All atoms occupy the 8c general position for this space group. In these refined structures, silicon and X atoms are ordered onto separate tetrahedrally coordinated sites (T-sites).

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