K2ZrSi3O9
hP30
(176) P63/m – ih2fb
K2ZrSi3O9 [2], wadeite
Structural features: Rings of three vertex-linked SiO4 tetrahedra share vertices with ZrO6 octahedra to
form a 3D-framework. Ordering variant of K2Si4O9. See Fig. IV.60.
Fig. IV.60. K2ZrSi3O9
Arrangement of ZrO6 octahedra
(light), SiO4 tetrahedra (dark) (O
atoms small) and K atoms (large).
Ferreira P. et al. (2001) [1]
K2O9Si3Zr
a = 0.69291, c = 1.01848 nm, c/a = 1.470, V = 0.4235 nm3, Z = 2
site
Wyck. sym.
x
y
z
occ.
atomic environment
__________________________________________________________________________________________________________________________________________________________________________
O1
Si2
O3
K4
Zr5
12i
6h
6h
4f
2b
1
m..
m..
3..
-3..
0.2562
0.3859
0.6036
1
/3
0
0.0225
0.127
0.0942
2
/3
0
0.1185
/4
1
/4
0.0572
0
1
single atom Si
tetrahedron O4
non-colinear Si2
non-coplanar triangle O3
octahedron O6
__________________________________________________________________________________________________________________________________________________________________________
Transformation from published data: y,x,-z
Experimental: powder, diffractometer, X-rays, Rp = 0.055
References: [1] Ferreira P., Ferreira A., Rocha J., Soares M.R. (2001), Chem. Mater. 13, 355-363. [2]
Henshaw D.E. (1955), Mineral. Mag. J. Mineral. Soc. 30, 585-595.
Landolt-Börnstein
New Series III/43A4