Design Rule of Multi-Dimensional Ternary Materials

Earlier, many physicists and chemists systematically described the crystal structure in chemical spaces of binary system using only information such as chemical elements and stoichiometry. Still, researchers use heuristic limits, chemical intuition, or rules of thumb to estimate the likelihood to estimate probable structure in more general and complex system such as ternary chemical space. In this work, for the realization of new <i>unknown</i> III-V(III: Al,In,Ga; V:P,As,Sb)-based ternary compounds, we attempted to derive additional insights from computational screening by examining the similarities between 1) high-throughput(HT) screening and 2) classical frameworks for crystal structure classification. For the HT screening, we have predicted the structural framework (cation-eutaxy) of <i>unknown</i> ternary <i>A</i>-<i>B</i>-<i>X </i>(<i>A</i>=alkaline, alkaline earth, <i>B</i>=transition metal, main group, <i>X</i>=O,S,Se,Te,N,P,As,Sb,Bi) compounds via algorithmic methodology using ‘structure prototypes’ consisting of metadata such as space group, stoichiometry, and # of sites. As a comparison, we propose a generalized description of the dimensionality of ternary <i>A</i>-<i>B</i>-<i>X </i>by competition among metallic, covalent, and ionic character of <i>A-X</i>/<i>B-X</i> bonding. The general description is an extension of van Arkel-Ketelaar diagram, describing ionic/covalent/metallic bonding characteristics of binary <i>AB</i> compounds using average configuration energy(CE) and difference in CE of <i>A</i>/<i>B</i> constituents, to ternary composition. Interestingly, 575 <i>unknown</i> suggested compounds acquired from our HT screening are found to be well-consistent with the classification of known cation-eutaxy compounds by our extended van Arkel-Ketelaar diagram. This result evidences that our algorithmic classification (HT screening) provides an effective descriptor for the dimension of the <i>B</i>-<i>X</i> network in <i>A</i>-<i>B</i>-<i>X</i> ternary chemical space. Our approach guides the discovery of <i>unknown</i> van der Waals materials with unique properties. We also demonstrated memristive devices for gate-tunable synaptic and logic functions using van der Waals crystals of prospective III-V semiconductors,¹ which is promising for neuromorphic and in-memory computing.<br/><br/>Reference<br/>J. Bae, J. Won, T. Kim, S. Choi, H. Kim, S.-H.V. Oh, G. Lee, E. Lee, S. Jeon, M. Kim, H.W. Do, D. Seo, S. Kim, Y. Cho, H. Kang, B. Kim, H. Choi, J. Han, T. Kim, N. Nemati, C. Park1, K. Lee, H. Moon, J. Kim, H. Lee, D.W. Davies, D. Kim, S. Kang, B. Yu, J. Kim, M.K. Cho, J.-H. Bae, S. Park, J. Kim, H.-J. Sung, M.-C. Jung, I. Chung, H. Choi, H. Choi, D. Kim, H. Baik, J.-H. Lee, H. Yang, Y. Kim, H.-G. Park, W. Lee, K.J. Chang, M. Kim, D.W. Chun, M.J. Han, A. Walsh, A. Soon,* J. Cheon,* C. Park,* J.-Y. Kim,* W. Shim* ”Cation-eutaxy enabled III-V-derived van der Waals crystals as memristive semiconductors”, <i>Nature Mater.</i> (2024). https://doi.org/10.1038/s41563-024-01986-x.