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Understanding the geometric diversity of inorganic and hybrid frameworks through structural coarse-graining.

ABSTRACT: Much of our understanding of complex structures is based on simplification: for example, metal-organic frameworks are often discussed in the context of "nodes" and "linkers", allowing for a qualitative comparison with simpler inorganic structures. Here we show how such an understanding can be obtained in a systematic and quantitative framework, combining atom-density based similarity (kernel) functions and unsupervised machine learning with the long-standing idea of "coarse-graining" atomic structure. We demonstrate how the latter enables a comparison of vastly different chemical systems, and we use it to create a unified, two-dimensional structure map of experimentally known tetrahedral AB₂ networks - including clathrate hydrates, zeolitic imidazolate frameworks (ZIFs), and diverse inorganic phases. The structural relationships that emerge can then be linked to microscopic properties of interest, which we exemplify for structural heterogeneity and tetrahedral density.

SUBMITTER: Nicholas TC

PROVIDER: S-EPMC8162807 | biostudies-literature | 2020 Oct

REPOSITORIES: biostudies-literature

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Understanding the geometric diversity of inorganic and hybrid frameworks through structural coarse-graining.

Nicholas Thomas C TC Goodwin Andrew L AL Deringer Volker L VL

Chemical science 20201019 46

Much of our understanding of complex structures is based on simplification: for example, metal-organic frameworks are often discussed in the context of "nodes" and "linkers", allowing for a qualitative comparison with simpler inorganic structures. Here we show how such an understanding can be obtained in a systematic and quantitative framework, combining atom-density based similarity (kernel) functions and unsupervised machine learning with the long-standing idea of "coarse-graining" atomic stru ...[more]

PMID: 34123235

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Dataset Information

Understanding the geometric diversity of inorganic and hybrid frameworks through structural coarse-graining.

Publications

Understanding the geometric diversity of inorganic and hybrid frameworks through structural coarse-graining.

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