Monthly Archives: July 2014

#100

#100

P4bm

Example – Na0.5Bi0.5TiO3

Investigation of the structure and phase transitions in the novel A-site substituted distorted perovskite compound Na0.5Bi0.5TiO3

Jones, G.O.; Thomas, P.A.
Acta Cryst. B (2002) 58, 168-178

CIF
https://www.dropbox.com/s/t3deu9mgrr0pheu/icsd_280984.cif

Na0.5Bi0.5TiO3

TiO6 octahedra (blue)
Na/Bi (yellow/green)

3D rotatable model of Na0.5Bi0.5TiO3

#97

#97

I422

Example – Ekanite, ThCa2Si8O20

Named for F.L.D. Ekanayake, of Colombo, Sri Lanka, who discovered the mineral.

A mineralogical study and crystal-structure determination of nonmetamict ekanite, ThCa2Si8O20

Szymanski J T, Owens D R, Roberts A C, Ansell H G, Chao G Y
The Canadian Mineralogist 20 (1982) 65-75

http://webmineral.com/data/Ekanite.shtml

CIF
http://rruff.geo.arizona.edu/AMS/download.php?id=05678.cif&down=cif

Ekanite

SiO4 tetrahedra (yellow)
ThO8 polyhedra (green)
CaO8 polyhedra (blue)

3D rotatable model of Ekanite

#96

#96

P43212

Example – Li(AlSi2O6)

Framework distortion by large ions in MAlSi2O6 aluminosilicates with keatite structure

Baumgartner, B.; Mueller, G.
European Journal of Mineralogy (1990) 2, 155-162

CIF
https://www.dropbox.com/s/09x3r4hxenbzykx/icsd_69394.cif

Li(AlSi2O6)

Al/SiO4 tetrahedra (orange)
Li (blue)

3D rotatable model of Li(AlSi2O6)

#94

#94

P42212

Example – Zn2(L) • 4 H2O, L = 4,4‘-bipyridine-2,6,2‘,6‘-tetracarboxylic acid

A Porous Framework Polymer Based on a Zinc(II) 4,4‘-Bipyridine-2,6,2‘,6‘-tetracarboxylate: Synthesis, Structure, and “Zeolite-Like” Behaviors

X. Lin, A.J. Blake, C. Wilson, X. Zhong Sun, N.R. Champness, M.W. George, P. Hubberstey, R. Mokaya, and M. Schröder
J. Am. Chem. Soc., 2006, 128 (33), pp 10745–10753

CIF
http://pubs.acs.org/doi/suppl/10.1021/ja060946uja060946usi20060215_033141.cif

Zn2L-bipy_tetracarboxylat

 

3D rotatable model of Zn2(L) • 4 H2O

#93

#93

P4222

This is also an interesting entry because space group #93 is as rarely occupied as space group #89 (P422).

In the paper of Urusov and Nadezhina it is mentioned that according to an investigation of Baur and Kassner in the year 1992 inorganic representatives of this space group are even absent.

Indeed, the ICSD retrieves 0 hits for this space group!

However, there are 6 hits in the CCDC, and for 4 of them also coordinate sets are given.

Example – Tetraphenylarsonium tetrakis(dimethyldithiophosphinato-S,S’)-cerium

Crystal and molecular structures of [AsPh4][Ln(S2PMe2)4] (Ln = Ce or Tm) and their comparison with results obtained from paramagnetic nuclear magnetic resonance data in solution

St.Spiliadis, A.A. Pinkerton, D. Schwarzenbach
J. Chem. Soc., Dalton Trans., 1982, 1809-1813

CIF
http://1drv.ms/1o8NZRa

BIYYOX

C (black)
As (purple)
P (orange)
S (yellow)
Ce (lime)

3D rotatable model of [AsPh4][Ln(S2PMe2)4]