New tetragonal tungsten-bronze-related phases in the pseudobinary system KNb3O8-Nb3O7F studied by high resolution electron microscopy and X-ray powder diffraction

1988 ◽  
Vol 137 (1-2) ◽  
pp. 163-179 ◽  
Author(s):  
Monica Lundberg ◽  
Margareta Sundberg
Keyword(s):  
Electron Microscopy ◽  
High Resolution ◽  
Powder Diffraction ◽  
Tungsten Bronze ◽  
High Resolution Electron Microscopy ◽  
Pseudobinary System ◽  
Tetragonal Tungsten Bronze ◽  
X Ray ◽  
Resolution Electron

scholarly journals High Resolution Electron Microscopy and X-Ray Powder Diffraction Studies of Sr2Nb5O9.

1990 ◽  
Vol 44 ◽  
pp. 222-227 ◽  
Author(s):  
Gunnar Svensson ◽  
Josephine Bahr ◽  
Björn Lüning ◽  
David T. Beattie ◽  
Povl Krogsgaard-Larsen ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
High Resolution ◽  
Powder Diffraction ◽  
High Resolution Electron Microscopy ◽  
X Ray ◽  
Resolution Electron

Structural studies by high-resolution electron microscopy: intergrowth of ReO3 and tetragonal tungsten bronze-type structures in the system Nb2O5–WO3

1978 ◽  
Vol 34 (6) ◽  
pp. 922-931 ◽  
Author(s):  
S. Iijama
Keyword(s):  
Electron Microscopy ◽  
High Resolution ◽  
Binary System ◽  
Crystal Structures ◽  
Tungsten Bronze ◽  
High Resolution Electron Microscopy ◽  
Host Lattice ◽  
Structural Studies ◽  
Tetragonal Tungsten Bronze ◽  
Resolution Electron

With high-resolution electron microscopy new crystal structures were found in the binary system of Nb2O5WO3 oxides. The compounds are proposed to have the mole ratios 4Nb2O5. 22WO3 and 4Nb2O5. 50WO3. The crystal structures are ascribed to intimate intergrowths of two known structures, the ReO3 type and tetragonal tungsten bronze type. The latter grows coherently in the host lattice of the former, forming regularly arranged slabs. The coherent intergrowth of the tetragonal tungsten bronze structures is described as the 'rotation operation' on the ReO3-type structure.

Structure of Nd10W22O81 from high-resolution electron microscopy and X-ray powder diffraction

2001 ◽  
Vol 57 (1) ◽  
pp. 13-19 ◽  
Author(s):  
Carl Grenthe ◽  
Antonietta Guagliardi ◽  
Margareta Sundberg ◽  
Per-Erik Werner
Keyword(s):  
Electron Microscopy ◽  
High Resolution ◽  
Powder Diffraction ◽  
High Resolution Electron Microscopy ◽  
X Ray ◽  
Transmission Electron ◽  
Resolution Electron ◽  
Cell Dimensions ◽  
New Type ◽  
Unit Cell Dimensions

The crystal structure of Nd10W22O81, neodymium tungstate, has been determined using a combination of high-resolution transmission electron microscopy and X-ray powder diffraction methods. The unit-cell dimensions determined from X-ray data are a  =  3.8613 (1), b  =  35.9431 (1), c  =  21.8900 (1) Å, V = 3038.05 Å3, Z  =  2, space group Pbcm. The structure is built up of pentagonal columns (PCs) connected to ReO3-type fragments consisting of three octahedra, thus forming W9O32 units. These units form `pillars' along a. These `pillars' are joined by pairs of tilted octahedra (W2O11 groups) to form corrugated layers perpendicular to b. The Nd atoms are located in the space between these layers and form the only link between them. Interstitial O atoms are located between two of the Nd atoms. The formula Nd10W22O81 can thus be alternatively given as Nd5W11O39 + x (x ≃ 1.5), where x represents the interstitial O atoms. Nd10W22O81 is a new type of PC structure.

Sign in / Sign up

Export Citation Format

Share Document