Database of Disordered Zeolite Structures
 
Intergrowth Family Pentasil
Periodic Building Unit
 
  Periodic Building Unit (PerBU): pentasil layer  
 
  Layer symmetry P 1 m (1)  
 
 
  References

    Perego, G. and Cesari, M.
   "Ordered and Disordered Structures in Borosilicates with a Pentasil-Type Framework"
  J. Appl. Crystallogr., 17, 403-410 (1984)

Connectivity pattern
Examples
The layers are stacked along the [100] 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 MFI
 
Cell Parameters: orthorhombic P n m a (# 62)
    a = 20.0900 Å b = 19.7380 Å c = 13.1420 Å  
  α = 90.0000° β = 90.0000° γ = 90.0000°  
Ring sizes (# T-atoms): 10 6 5 4  
Channel dimensionality: Topological (pore opening > 6-ring): 3-dimensional  
Channel system: {[100] 10 5.1 x 5.5 <-> [010] 10 5.3 x 5.6}***  
 
In this space group and setting, the PerBUs are stacked along [100]
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 MFI
 
 
  Polymorph MEL
 
Cell Parameters: tetragonal I -4 m 2 (# 119)
    a = 20.2700 Å b = 20.2700 Å c = 13.4590 Å  
  α = 90.0000° β = 90.0000° γ = 90.0000°  
Ring sizes (# T-atoms): 10 8 6 5 4  
Channel dimensionality: Topological (pore opening > 6-ring): 3-dimensional  
Channel system: <100> 10 5.3 x 5.4***  
 
In this space group and setting, the PerBUs are stacked along [100]
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 MEL
 
Disorder Example
 
  Simple example of a random stacking
 
  Adjacent layers generated by the same connectivity pattern (same basic color) are shown with different shades for clarity
There is no blocking of the 3D channel system.