Property directed generative design of inorganic materials

EXTENDED ABSTRACT: A combination of AI, high-throughput experiments (robotics) and high-performance simulations can be used to accelerated materials development. For inorganic crystalline materials, structure determines property. Therefore, property-driven generative design, driven by machine learning, critically requires understanding of the structure of materials. A deep understanding of crystal structures and their symmetries is essential for accurate generative design.Thus, the development of symmetry-aware generative models becomes critical to ensure property-directed learning branches. Further, generated crystal structures require validation, both computationally and experimentally. First, I will introduce a generative design framework (WyCryst) [1], composed of three pivotal components: 1) a Wyckoff position based inorganic crystal representation, 2) a property-directed VAE model and 3) an automated DFT workflow for structure refinement. We successfully reproduce a variety of existing materials for both ground state as well as polymorphic structure predictions. We also generate several new ternary materials not found in the inorganic materials databases, which are proved to be stable, retaining their symmetry, and we also check their phonon stability, using our automated DFT workflow highlighting the validity of our approach [2]. We believe our symmetry-aware WyCryst takes a vital step towards AI-driven inorganic materials discovery. Next, we address the challenge of experimental synthesis of these materials paired with data-driven characterization techniques to assess their properties. This is challenging due to the lack of a general method to rapidly synthesize and (optimally) dope bulk materials. We invented a rapid self-sintered solid-state synthesis technique (tested on GeTe, Copper, Silver Antimony Telluride), achieving phase-pure crystalline materials synthesized in the milligram scale in as little as 15 seconds. This accelerates the solidstate reaction process by a factor of >100 relative to the traditional route of mix-and-bake and produce direct experimental validation.


Keywords: AI4Science, Machine Learning for Materials, Generative Design, DFT, ML interatomic potentials, high-throughput synthesis
REFERENCES:
[1]Ruiming Zhu, Wei Nong, Shuya Yamazaki, Kedar Hippalgaonkar, WyCryst: Wyckoff Inorganic Crystal Generator Framework, Cell Press
Matter (2024) DOI: 10.1016/j.matt.2024.05.042
[2]Wei Nong, Ruiming Zhu, Kedar Hippalgaonkar, CrySP

Brief Introduction of Speaker
Kedar Hippalgaonkar

Associate Professor Kedar Hippalgaonkar’s research interests are in AI-driven solid-state materials-bydesign. He holds a joint appointment as an associate professor with the Materials Science and Engineering Department at NTU, and as a Principal Scientist at IMRE, A*STAR. He was the Scientific Director of the Multi-PI S$25M Accelerated Materials Development for Manufacturing (AMDM) program from 2018 – 2024, and S$10M Materials Generative Design and Testing Framework program (Mat-GDT) from 2024-2027. Leading a group of >30 members, he has demonstrated clear areas of advancement in the discovery of new functional materials, AI and robotics for accelerated materials discovery, and advancing fundamental knowledge in inequilibrium charge and phonon scattering. His scientific contributions in the materials-bydesign space have established a framework for the rapid discovery of materials and new physics, which is now being utilised globally in data-driven research. His commitment to translating scientific research into tangible real-world applications is exemplified by his role as the Co-founder and Senior Scientific Advisor of a startup – Xinterra, Inc. As a contributing member of the newly established Acceleration Consortium at the University of Toronto, Kedar collaborates with an international community of scientists dedicated to the creation of materials acceleration platforms. These platforms are pivotal in unlocking new discoveries in molecules and materials, further expanding the horizon of scientific understanding.