Database of Disordered Zeolite Structures
 
Intergrowth Family PST-24
2-dimensional disorder of the units connecting ordered columns
Periodic Building Unit
 
  Periodic Building Unit (PerBU): cas-zz column  
  Column symmetry -1  
  2D cell parameters a = 5.10 Å b = 21.30 Å gamma = 90°    
  Comment To facilitate understanding of the connectivity patterns shown below, O atoms that connect to the two types of rows of double 5-ring (d5r) unit connectors have been highlighted in red in the cas-zz unit shown to the right.  
 
Arrangement of columns
  Symmetry -1  
  3D cell parameters a = 23.70 Å b = 5.0800 Å c = 21.30 Å
    alpha = 90.0° beta = 111.8° gamma = 90.0°    
  Comment The 3-dimensional arrangement of the columns (related by inversion centers).  
Connecting unit
  Connecting unit d5r    
 
References
 
    Jo, D., Zhao, J., Cho, J., Lee, J.H., Liu, Y., Liu, C., Zou, X. and Hong, S.B.
   "PST-24: a zeolite with varying intracrystalline channel dimensionality"
   Angew. Chem. Int. Ed., 59, 17691-17696 (2020)

Connectivity pattern
Examples

Positions of d5r unit connectors above the cas-zz column
The position of the first d5r unit in a row (along a) determines the positions of all other d5r units in that row.
There are two types of rows, one connecting the cas-zz columns along b, and one connecing them along c. Those of the first type have translations of 0, or 1/2 along a and those of the second type 1/4 or 3/4. In the description below, these four positions are numbered from 1 to 4 with increasing translation along a, and are color coded (1: blue, 2: light blue, 3: orange, 4: red).
Once the position of the first row of d5r units is fixed (position 1 or 3), there are two possible positions for the second row (position 2 or 4).

 
Row 1 Translation Row 2 Translation Image
position 1
0.a
position 2
1/4a
position 1
0.a
position 4
3/4a
position 3
1/2.a
position 2
1/4a
position 3
1/2.a
position 4
3/4a
Examples

Disorder along b
The arrangement of the rows of d5r units is not necessarily periodic along b.
Four possible arrangements of d5r rows above two cas-zz columns are shown below.

 
Row 1 Row 2 Row 3 Row 4 Image
Example 1
position 1
position 2
position 1
position 2
Example 2
position 1
position 2
position 3
position 2
Example 3
position 1
position 2
position 1
position 4
Example 4
position 1
position 2
position 3
position 4
An example showing disorder in the rows of d5r units connecting the ordered cas-zz columns.

Disorder along c
Although the cas-zz columns are arranged periodically in 3 dimensions (see Periodic Building Unit above), the rows of d5r units connecting them are disordered along both b and c. The highlighted section in the image on the right corresponds to Example 1 above. The four different colors indicate the four possible positions of the d5r units along a.
Translations for positions 1-4: 0a (blue); 1/4a (light blue); 1/2a (orange); 3/4a (red).



Effect on channel system
The disorder does not block the straight channels along a. However the connections between these channels are affected by the placement of the rows of connecting units. (see the simple polymorph examples below).

Simplest ordered end-members
The PerBu (cas-zz columns) are always in gray.
The color scheme for the d5r connectors are given in table 1.

 
  Polymorph PST-24_A
 
Cell Parameters: monoclinic P 1 21/c 1 (# 14)
  a = 25.0725 Å b = 10.1658 Å c = 23.4799 Å  
  α = 90.0000° β = 128.6230° γ = 90.0000°  
  Volume = 4675.6 Å3
Framework Density (FDSi): 18.8
Ring sizes (# T-atoms): 10  8  6  5  4    
Channel dimensionality: Topological (pore opening > 6-ring): 2-dimensional  
  Maximum diameter of a sphere:  
    that can be included 5.36 Å  
    that can diffuse along a:  1.76 Å b:  4.67 Å c:  1.76 Å  
    [101] :  3.67 Å
    addional volume data  
In this space group and setting the ordered cas-zz columns run parallel to the [010] direction.
Note: This polymorph has NOT been observed as a pure ordered material
 
 
  Polymorph PST-24_B
 
Cell Parameters: triclinc P -1 (# 2)
  a = 23.4569 Å b = 10.2358 Å c = 21.1671 Å  
  α = 90.1560° β = 111.9470° γ = 89.8490°  
  Volume = 4713.9 Å3
Framework Density (FDSi): 18.7
Ring sizes (# T-atoms): 10  8  6  5  4    
Channel dimensionality: Topological (pore opening > 6-ring): 2-dimensional  
  Maximum diameter of a sphere:  
    that can be included 5.66 Å  
    that can diffuse along a:  1.86 Å b:  4.7 Å c:  3.63 Å  
    addional volume data  
In this space group and setting the ordered cas-zz columns run parallel to the [010] direction.
Note: This polymorph has NOT been observed as a pure ordered material
 
 
  Polymorph PST-24_C
 
Cell Parameters: monoclinic P 1 2/c 1 (# 13)
  a = 25.1333 Å b = 10.1720 Å c = 23.5362 Å  
  α = 90.0000° β = 128.7040° γ = 90.0000°  
  Volume = 4695.7 Å3
Framework Density (FDSi): 18.7
Ring sizes (# T-atoms): 10  8  6  5  4    
Channel dimensionality: Topological (pore opening > 6-ring): 3-dimensional  
  Maximum diameter of a sphere:  
    that can be included 5.57 Å  
    that can diffuse along a:  3.51 Å b:  4.6 Å c:  3.51 Å  
    addional volume data  
In this space group and setting the ordered cas-zz columns run parallel to the [010] direction.
Note: This polymorph has NOT been observed as a pure ordered material
 

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