Graph-based discovery and analysis of atomic-scale one-dimensional materials

Recent decades have witnessed an exponential growth in the discovery of low-dimensional materials (LDMs), benefiting from our unprecedented capabilities in characterizing their structure and chemistry with the aid of advanced computational techniques. Recently, the success of two-dimensional compounds has encouraged extensive research into one-dimensional (1D) atomic chains. Here, we present a methodology for topological classification of structural blocks in bulk crystals based on graph theory, leading to the identification of exfoliable 1D atomic chains and their categorization into a variety of chemical families. A subtle interplay is revealed between the prototypical 1D structural motifs and their chemical space. Leveraging the structure graphs, we elucidate the self-passivation mechanism of 1D compounds imparted by lone electron pairs, and reveal the dependence of the electronic band gap on the cationic percolation network formed by connections between structure units. This graph-theory-based formalism could serve as a source of stimuli for the future design of LDMs.

Automated summary

In recent decades, there has been exponential growth in the discovery of low-dimensional materials (LDMs) due to advances in computational techniques. The success of two-dimensional compounds has led to extensive research on one-dimensional (1D) atomic chains. In this study, the authors introduce a methodology based on graph theory for the topological classification of structural blocks in bulk crystals, resulting in the identification and categorization of exfoliable 1D atomic chains into different chemical families. The authors reveal a subtle interplay between prototypical 1D structural motifs and their chemical space, and explore the self-passivation mechanism and the dependence of electronic band gap on the cationic percolation network formed by connections between structure units. This graph-theory-based formalism provides insights for the future design of LDMs.