Supplementary Data--Crystal Data and Structure Refinement for Methyl (−)-Dimentylmalonate 4a

2002 ◽  
Vol 7 (6) ◽  
pp. 333-337
Keyword(s):  
Structure Refinement ◽  
Supplementary Data ◽  
Crystal Data

Ideal and Real Structure of Ti5O4(PO4)4: X-ray and HRTEM Investigations

1998 ◽  
Vol 54 (6) ◽  
pp. 722-731 ◽  
Author(s):  
F. Reinauer ◽  
R. Glaum
Keyword(s):  
Crystal Structure ◽  
Electron Microscopy ◽  
Structure Refinement ◽  
Ideal Structure ◽  
Crystal Data ◽  
Asymmetric Unit ◽  
X Ray Diffraction ◽  
X Ray ◽  
Transmission Electron ◽  
The Ideal

The crystal structure of pentatitanium tetraoxide tetrakis(phosphate), Ti5O4(PO4)4, has been determined and refined from X-ray diffraction single-crystal data [P212121 (No. 19), Z = 4, a = 12.8417 (12), b = 14.4195 (13), c = 7.4622 (9) Å (from Guinier photographs); conventional residual R 1 = 0.042 for 2556 Fo > 4σ(Fo ), R 1 = 0.057 for all 3276 independent reflections; 282 parameters; 29 atoms in the asymmetric unit of the ideal structure]. The structure is closely related to those of β-Fe2O(PO4)-type phosphates and synthetic lipscombite, Fe3(PO4)4(OH). While these consist of infinite chains of face-sharing MO6 octahedra, in pentatitanium tetraoxide tetrakis(phosphate) only five-eighths of the octahedral voids are occupied according to □3Ti5O4(PO4)4. Four of the five independent Ti4+O6 show high radial distortion [1.72 ≤ d(Ti−O) ≤ 2.39 Å] and a typical 1 + 4 + 1 distance distribution. The fifth Ti4+O6 is an almost regular octahedron [1.91 ≤ d(Ti−O) ≤ 1.98 Å]. Partial disorder of Ti4+ over the available octahedral voids is revealed by the X-ray structure refinement. High-resolution transmission electron microscopy (HRTEM) investigations confirm this result.

Die Synthese und Struktur von Clusteraziden: A4[Nb6Cl12(N3)6](H2O)2 mit A=Rb. Cs / Synthesis and Structure of the Cluster Azides: A4Nb6Cl12(N3)6](H2O)2 with A=Rb, Cs

1995 ◽  
Vol 50 (9) ◽  
pp. 1377-1381 ◽  
Author(s):  
Olaf Reckeweg ◽  
H.-Jürgen Meyer
Keyword(s):  
Single Crystal ◽  
Structure Refinement ◽  
Three Dimensional ◽  
Dimensional Structure ◽  
Crystal Data ◽  
Mechanical Pressure ◽  
Space Group ◽  
X Ray ◽  
Methanolic Solution ◽  
New Compounds

AbstractThe new compounds A4[Nb6Cl12(N3)6](H2O)2 (A = Rb, Cs) were synthesized from In4[Nb6Cl12Cl6] by substituting six terminal Cl ligands and the In+ ions in methanolic solution. An X-ray structure refinement was performed on single-crystal data of Rb4[Nb6Cl12(N3)6](H2O)2 (1) (space group P1̄, Z = 1, a = 912.5(1) pm, b = 937.2(1) pm, c = 1062.0(1) pm, α = 96.88(2)°, β = 101.89(1)°, γ = 101.44(2)°) and Cs4[Nb6Cl12(N3)6](H2O)2 (2) (space group PI, Z = 1, a = 920.9(5) pm, b = 947.9(7) pm, c = 1091.8(7) pm, α = 96.89(6)°, β = 103.35(5)°, γ = 101.60(5)°. Each of the centrosymmetric [Nb6Cl12(N3)6]4- ions of the isotypic compounds contains six terminal azide groups at the corners of the octahedral niobium cluster (d̄Nb-N = 226(1) pm (1), 225(1) pm (2), bond angles Nb-N-N 120-127°). The [Nb6Cl12(N3)6]4- ions are linked via Rb-N and Rb-Cl interactions of the Rb+ ions to form a three-dimensional structure. Crystals of the compounds react explosively on heating or mechanical pressure.

Rietveld powder structure refinement of Na2Al2Ti6O16; Comparison of synchrotron radiation and conventional x-ray tube datasets

1990 ◽  
Vol 5 (7) ◽  
pp. 1538-1543 ◽  
Author(s):  
H. Toraya ◽  
N. Masciocchi ◽  
W. Parrish
Keyword(s):  
Crystal Structure ◽  
Synchrotron Radiation ◽  
Chemical Analysis ◽  
Rietveld Method ◽  
Structure Refinement ◽  
Site Occupancy ◽  
Partial Ordering ◽  
Crystal Data ◽  
X Ray ◽  
Octahedral Sites

The crystal structure of Na2Al2Ti6O16 was refined by the Rietveld method using synchrotron radiation and conventional x-ray powder data, and the agreement factors were Rp = 3.35%, Rwp = 4.30%, and RBragg = 6.39% for synchrotron data. The formula based on the chemical analysis and 16 O atoms is Na1.97Al1.82Ti6.15O16. The crystal data are monoclinic, C2/m, a = 12.1239(3) Å, b = 3.7749(1) Å, c = 6.4180(2) Å, β = 107.59(1)°, V = 280.00(4) Å3, Z = 1, and Dx = 3.82 g cm−3. The site occupancy refinement showed a partial ordering of Al3+ and Ti4+ ions in the two-crystallographically independent octahedral sites.

Structure refinement of Cu8GeS6 using X-ray diffraction data from a multiple-twinned crystal

1999 ◽  
Vol 55 (5) ◽  
pp. 721-725 ◽  
Author(s):  
Mitsuko Onoda ◽  
Xue-An Chen ◽  
Katsuo Kato ◽  
Akira Sato ◽  
Hiroaki Wada
Keyword(s):  
Diffraction Data ◽  
Room Temperature ◽  
Structure Refinement ◽  
Unit Cell ◽  
Temperature Phase ◽  
Crystal Data ◽  
X Ray Diffraction ◽  
X Ray ◽  
Germanium Sulfide ◽  
Symmetry Operations

The structure of the orthorhombic room-temperature phase of Cu8GeS6 (copper germanium sulfide), Mr = 773.27, has been refined on the basis of X-ray diffraction data from a 12-fold twinned crystal applying a six-dimensional twin refinement technique. For 1804 unique reflections measured using Mo Kα radiation, RF was 0.083 with 77 structure parameters and 12 scale factors. The symmetry operations, the unit cell and other crystal data are (0, 0, 0; ½, ½, 0) + x, y, z; y, x, z; ¼ − x, ¾ − y, ½ + z; ¾ − y, ¼ − x, ½ + z; a = b = 9.9073 (3) Å, c = 9.8703 (4) Å, α = β = 90°, γ = 90.642 (4)°; V = 968.7 (1) Å3, Z = 4, Dx  = 5.358 Mg m−3, μ = 21.70 mm−1. The standard setting of the space group and the reduced unit cell are Pmn21; a = 7.0445 (3), b = 6.9661 (3), c = 9.8699 (5) Å; Z = 2.

scholarly journals Structure Refinement of Ti5Sb3 from Single-crystal Data.

1977 ◽  
Vol 31a ◽  
pp. 889-890 ◽  
Author(s):  
Rolf Berger ◽  
N. W. Larsen ◽  
H. Svanholt ◽  
Michel Pouchard ◽  
Paul Hagenmuller ◽  
...  
Keyword(s):  
Single Crystal ◽  
Structure Refinement ◽  
Crystal Data

Powder Rietveld refinement of armstrongite, CaZr[Si6O15]·3H2O

2000 ◽  
Vol 215 (12) ◽  
Author(s):  
D.Yu. Pushcharovsky ◽  
K. Kabalov ◽  
N.V. Zubkova ◽  
J. Schneider ◽  
A.N. Sapozhnikov
Keyword(s):  
Rietveld Refinement ◽  
Structure Refinement ◽  
Rietveld Analysis ◽  
Crystal Data ◽  
X Ray Diffraction ◽  
X Ray

Crystal data and results of structure refinement using powder X-ray diffraction and Rietveld analysis for armstrongite, CaZr[Si

Sign in / Sign up

Export Citation Format

Share Document