Database of Zeolite Structures
Framework Type *CTH
Cell Parameters: orthorhombic C m c m (# 63)
    a = 10.4578 Å b = 27.7607 Å c = 27.2023 Å  
  α = 90.000° β = 90.000° γ = 90.000°  
Volume = 7897.3 Å3  
RDLS = 0.0059  
  Framework density (FDSi): 16.2 T/1000 Å3  
  Topological density: TD10 = 859  
Ring sizes (# T-atoms): 14  10  6  5  4    
Channel dimensionality: Topological (pore opening > 6-ring): 2-dimensional  
  Maximum diameter of a sphere:  
  that can be included 8.14 Å  
that can diffuse along a:   7.45 Å b:   3.92 Å c:   2.22 Å  
Accessible volume: 17.22   %  
Composite Building Units:
d4r (t-cub )
non (t-non )
Natural Tiling t-pes t-cub t-non t-cth-1 t-cth-2 t-cth-3
* Disordered Type Material
The Type Material of this Framework Type is disordered. An ordered framwork structure is given here to facilitate the discription, but no bulk material with this stucture is presently known. A brief description of the disorder is given below. For more details see the original publication.
Brief description of the disorder
The disorder in *CTH can be described in terms of the ordering of the d4r (double 4-rings). On the right, two end-members, polymorph CTH-A and polymorph CTH-B, are shown (last 4 images in green). In CTH-A the d4r in adjacent layers perpedicular to [100] are shifted by (1/2,1/2,0) and in CTH-B by (1/2,1/2,1/2). In the main model above (polymorph CTH-C) these two positions of the d4r units alternate. It is assumed that the stacking of the d4r units is random in a normal synthesis.

Effect of the disorder on the channel system
The stacking order does not cause any blocking of the straight 14-ring channel. Although the 10-ring channels along [010] are not blocked by the disorder, they are no longer straight.
Framework images
(click on icon for larger image)

viewed along [100]

Projection along [100]
viewed along [010]
Projection along [010]
viewed along [001]
Projection along [001]
Building unit viewed normal to [001]
Polymorph CTH-A
viewed along [010]
Polymorph CTH-A
projection along [010]
Polymorph CTH-B
viewed along [010]
Polymorph CTH-B
projection along [010]


Year code assigned 2018
Data last updated Jul 17, 2018