Database of Disordered Zeolite Structures

Intergrowth Family **IM-18**

Periodic Building Unit

Periodic Building Unit (PerBU): | Layer of isolated zig-zag chains | ||

Layer symmetry | P m m (2) | ||

Comment | To facilitate understanding of the connectivity patterns shown below, O atoms that connect to a single row of d4r units have been highlighted in the layer of isolated zig-zag chains shown to the right. |
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Connector

Unit | d4r |
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Connectivity pattern

Examples |

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^{*} relative to the previous layer of connectorsPositions of d4r unit connectors in a rowThere are two possible positions for a row of d4r units above two neighboring zig-zag chains in the layer. The position of the first d4r unit (along a) determines the positions of all the other d4r units in that row.
Disorder along b: arrangements of the rows of d4r unit connectorsThe arrangement of the rows of d4r units is not necessarily periodic along b. Each row can be the same as the neighboring one or shifted by 1/2a. |

Effect on channel system | |

The disorder can block one or both of the straight 10-ring channels (e.g. those present in polymorphs A and B) when both d4r positions are present in a single layer of d4r units (see polymorph C). |

Simplest ordered end members

Connectors are shown in light blue.

Adjacent PerBUs generated by the same connectivity pattern (with or without connectors in between) are shown with different shades of the same color for clarity.

Adjacent PerBUs generated by the same connectivity pattern (with or without connectors in between) are shown with different shades of the same color for clarity.

Polymorph EOS | |||||

Cell Parameters: | monoclinic | P 1 2/m 1: (# 10) | |||

a = 9.0869 Å |
b = 7.5548 Å |
c = 10.4762 Å |
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α = 90.000° | β = 108.333° | γ = 90.000° | |||

Volume = | 682.7 Å^{3} |
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Framework Density (FD_{Si}): |
17.6 |

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 | 4.96 Å | ||||||

that can diffuse along | a: 3.72 Å | b: 4.43 Å | c: 3.01 Å | ||||

[0 1 0] : 4.43 Å | |||||||

addional volume data |

Composite Building Units: |

d4r | mtw | |||

Note: This polymorph corresponds to the ordered framework EOS | |

Polymorph IM-18_B | |||||

Cell Parameters: | orthorhombic | P m m a: (# 51) | |||

a = 17.1828 Å |
b = 7.5138 Å |
c = 10.4477 Å |
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α = 90.0000° | β = 90.0000° | γ = 90.0000° | |||

Volume = | 1348.9 Å^{3} |
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Framework Density (FD_{Si}): |
17.8 |

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 | 5.1 Å | ||||||

that can diffuse along | a: 3.88 Å | b: 4.54 Å | c: 2.88 Å | ||||

[0 1 0] : 4.54 Å | |||||||

addional volume data |

Composite Building Units: |

d4r | mtw | |||

In this space group and setting, the ordered connecting rows are along [001] and the layers are stacked along [100] |

Note: This polymorph has NOT been observed as a pure ordered material | |

Polymorph ITW | |||||

Cell Parameters: | monoclinic | C 1 2/m 1: (# 12) | |||

a = 10.4496 Å |
b = 15.0277 Å |
c = 8.9537 Å |
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α = 90.000° | β = 105.640° | γ = 90.000° | |||

Volume = | 1354.0 Å^{3} |
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Framework Density (FD_{Si}): |
17.7 |

Ring sizes (# T-atoms): | 8 6 5 4 | ||

Channel dimensionality: | Topological (pore opening > 6-ring): 2-dimensional |

Maximum diameter of a sphere: | |||||||

that can be included | 4.73 Å | ||||||

that can diffuse along | a: 2.78 Å | b: 1.54 Å | c: 3.95 Å | ||||

addional volume data |

Composite Building Units: |

d4r | ||

In this space group and setting, the ordered connecting rows are along [001] and the layers are stacked along [100] |

Note: This polymorph corresponds to the ordered framework ITW | |