Database of Disordered Zeolite Structures
 
Intergrowth Family SSZ-31
Periodic Building Unit
 
  Periodic Building Unit (PerBU): SSZ-31 layer  
 
  Layer symmetry  
 
  Comment The positions of the double crankshaft chains have been highlighted to facilitate the understanding of the relationships shown in the connectivity pattern table below  
 
  References

    Lobo, R.F., Tsapatsis, M., Freyhardt, C.C., Chan, I., Chen, C.-Y., Zones, S.I. and Davis, M.E.
   "A model for the structure of the large-pore zeolite SSZ-31"
  J. Am. Chem. Soc., 119, 3732-3744 (1997)

    van Koningsveld, H. and Lobo, R.F.
   "Disorder in zeolite SSZ-31 described on the basis of one-dimensional building units"
  J. Phys. Chem. B, 107, 10983-10989 (2003)

Connectivity pattern
Examples


 
Symmetry
Operation*
Translation* Comment Image
+2/6 a
  
+1/6 a
  
-1/6 a
  This is equivalent to +5/6 a or +2/6 a + 1/2 b $
-2/6 a
  This is equivalent to +4/6 a or +1/6 a + 1/2 b $
 

* relative to the previous layer

$ This equivlancy arises from the fact that the double crankshaft chains are at different positions along b

Note: It would also be possible to translate the layer by 0/6 a or 3/6 a, but this would result in a sequence of 6-6-4-rings in the connecting plane instead of the sequence of 6-5-5 rings seen in the ac-projections above. As this 6-6-4-ring sequence has not yet been observed, it is not included here.

Effect on channel system
  The disorder does not block the 1-dimensional channel system
Simplest ordered end members


 
  Polymorph E
 
Cell Parameters: monoclinic C 1 2/m 1 (# 12)
    a = 24.7010 Å b = 8.3900 Å c = 15.0010 Å  
  α = 90.0000° β = 105.5000° γ = 90.0000°  
Ring sizes (# T-atoms): 12 6 5 4  
Channel dimensionality: Topological (pore opening > 6-ring): 1-dimensional  
 
Note: This polymorph has NOT been observed as a pure ordered material
 
 
  Polymorph F
 
Cell Parameters: orthorhombic C m c a (# 64)
    a = 8.3900 Å b = 24.7010 Å c = 28.9100 Å  
  α = 90.0000° β = 90.0000° γ = 90.0000°  
Ring sizes (# T-atoms): 12 6 5 4  
Channel dimensionality: Topological (pore opening > 6-ring): 1-dimensional  
 
Note: This polymorph has NOT been observed as a pure ordered material
 
 
  Polymorph G
 
Cell Parameters: monoclinic C 1 2/m 1 (# 12)
    a = 24.7000 Å b = 8.4000 Å c = 16.5800 Å  
  α = 90.0000° β = 119.8000° γ = 90.0000°  
Ring sizes (# T-atoms): 12 6 5 4  
Channel dimensionality: Topological (pore opening > 6-ring): 1-dimensional  
 
Note: This polymorph has NOT been observed as a pure ordered material
 
 
  Polymorph H
 
Cell Parameters: orthorhombic C m c a (# 64)
    a = 8.3900 Å b = 24.7010 Å c = 28.9100 Å  
  α = 90.0000° β = 90.0000° γ = 90.0000°  
Ring sizes (# T-atoms): 12 6 5 4  
Channel dimensionality: Topological (pore opening > 6-ring): 1-dimensional  
 
Note: This polymorph has NOT been observed as a pure ordered material