Database of Disordered Zeolite Structures
 
Intergrowth Family CAS-NSI
Periodic Building Unit
 
  Periodic Building Unit (PerBU): CAS layer  
 
  Layer symmetry P 1 2/m (1)  
 
  2D cell parameters a = 14.13 Å b = 5.26 Å gamma = 90°    
 
  References

    B. Marler, M.A. Camblor, H. Gies
   "The disordered structure of silica zeolite EU-20b, obtained by topotactic condensation of the piperazinium containing layer silicate EU-19"
   Microporous Mesoporous Mater., 90, 87–101 (2006)

Connectivity pattern
Examples
The layers are stacked along the [001] direction using the following connectivity patterns

 
Symmetry
Operation*
Translation* Comment Image
i
none
  one inversion center shown as an open circle in the example
m
none
   mirror plane shown as a solid line in the example
 

* relative to the previous layer


 
Effect on channel system
  The disorder does not block the channel system
Simplest ordered end members
The color of each layer reflects the symmetry/translation operation used to generate it from the previous layer (see table above).

 
  Polymorph CAS
 
Cell Parameters: orthorhombic C m c m: (# 63)
  a = 5.2560 Å b = 14.1320 Å c = 17.2270 Å  
  α = 90.000° β = 90.000° γ = 90.000°  
  Volume = 1279.6 Å3
Framework Density (FDSi): 18.8
Ring sizes (# T-atoms): 8  6  5    
Channel dimensionality: Topological (pore opening > 6-ring): 1-dimensional  
  Maximum diameter of a sphere:  
    that can be included 5.05 Å  
    that can diffuse along a:  2.97 Å b:  2.21 Å c:  2.45 Å  
    addional volume data  
Composite Building Units:
cas
bik
In this space group and setting, the PerBUs are stacked along [001]
Adjacent layers generated by the same connectivity pattern (same basic color) are shown with different shades for clarity.
Note: This polymorph corresponds to the ordered framework CAS
 
 
  Polymorph NSI
 
Cell Parameters: monoclinic C 1 2/m 1: (# 12)
  a = 14.1287 Å b = 5.2535 Å c = 8.9277 Å  
  α = 90.000° β = 105.370° γ = 90.000°  
  Volume = 639.0 Å3
Framework Density (FDSi): 18.8
Ring sizes (# T-atoms): 8  6  5    
Channel dimensionality: Topological (pore opening > 6-ring): 1-dimensional  
  Maximum diameter of a sphere:  
    that can be included 4.16 Å  
    that can diffuse along a:  2.6 Å b:  3.3 Å c:  2.45 Å  
    addional volume data  
Composite Building Units:
cas
bik
In this space group and setting, the PerBUs are stacked along [001]
Adjacent layers generated by the same connectivity pattern (same basic color) are shown with different shades for clarity.
Note: This polymorph corresponds to the ordered framework NSI
 
Disorder Example
 
 
  Simple example of a random stacking of CAS and NSI polymorphs.
 
  There is no blocking of the 1D channel system.