Search results for "Automated electron diffraction tomography"
showing 3 items of 3 documents
MZ-35, a new layered pentasil borosilicate synthesized in the presence of large alkali cations
2013
Abstract A new layered borosilicate has been synthesized in the presence of cesium and sodium cations and its structure has been solved by a combination of automated diffraction tomography (ADT) and X-ray powder diffraction (XRPD). MZ-35 has a composition NaCs 2 [BSi 7 O 16 (OH) 2 ](OH) 2 ·4H 2 O and features space group P-4m2. The unusually small unit cell ( a 7.3081 A, c 10.7520 A) is shared by two random-stacked configurations of the structure: a network of connected pentasil units related to the layer of RUB-18 and a bidimensional checkerboard of intersecting ladders of 4-membered rings. The two configurations are related by the simple face-sharing inversion of a hydroxyl-bearing tetrah…
The structure of charoite, (K,Sr,Ba,Mn)(15-16)(Ca,Na)(32)[(Si-70(O,OH)(180))](OH,F)(4.0)center dot nH(2)O, solved by conventional and automated elect…
2010
AbstractCharoite, ideally (K,Sr,Ba,Mn)15–16(Ca,Na)32[(Si70(O,OH)180)](OH,F)4.0·nH2O, a rare mineral from the Murun massif in Yakutiya, Russia, was studied using high-resolution transmission electron microscopy, selected-area electron diffraction, X-ray spectroscopy, precession electron diffraction and the newly developed technique of automated electron-diffraction tomography. The structure of charoite (a= 31.96(6) Å,b= 19.64(4) Å,c= 7.09(1) Å, β = 90.0(1)°,V= 4450(24) Å3, space groupP21/m) was solvedab initioby direct methods from 2878 unique observed reflections and refined toR1/wR2= 0.17/0.21. The structure can be visualized as being composed of three different dreier silicate chains: a d…
Structure analysis of titanate nanorods by automated electron diffraction tomography
2011
A hitherto unknown phase of sodium titanate, NaTi3O6(OH)·2H2O, was identified as the intermediate species in the synthesis of TiO2 nanorods. This new phase, prepared as nanorods, was investigated by electron diffraction, X-ray powder diffraction, thermogravimetric analysis and high-resolution transmission electron microscopy. The structure was determined ab initio using electron diffraction data collected by the recently developed automated diffraction tomography technique. NaTi3O6(OH)·2H2O crystallizes in the monoclinic space group C2/m. Corrugated layers of corner- and edge-sharing distorted TiO6 octahedra are intercalated with Na+ and water of crystallization. The nanorods are typically …