LAX phases: A family of novel stable layered materials, informatics‐based discovery

• Published in: InfoMat Vol. 7; no. 7
• Main Authors: Alibagheri, Ehsan, Khazaei, Mohammad, Estili, Mehdi, Seyfi, Alireza, Mizoguchi, Hiroshi, Ohno, Kaoru, Hosono, Hideo, Vaez Allaei, S. Mehdi
• Format: Journal Article
• Language: English
• Published: Melbourne John Wiley & Sons, Inc 01.07.2025; Wiley
• Subjects: Algorithms; Carbon; Crystal structure; Crystals; Dynamic stability; Energy; evolutionary algorithm; Free energy; Heat of formation; LAX phases; Layered materials; Machine learning; materials discovery; materials informatics; Materials science; MAX phases; Mechanical properties; Metals; Modulus of elasticity; Nitrogen; Palladium; Phases; Symmetry; Transition metals
• ISSN: 2567-3165; 2567-3165
• DOI: 10.1002/inf2.12664

Ternary MAX phases, characterized by the chemical formula M₂AX, represent a group of layered materials with hexagonal lattices. These MAX phases have been the subject of extensive experimental and theoretical studies. Formation energy and thermodynamic calculations indicate that MAX phases containing late transition metals, such as Rh, Ru, Pt, Pd, Co, and Ni, are unlikely to form. Here, we introduce an alternative family of orthorhombic and monoclinic materials, the LAX phases, which exhibit similarities to MAX phases in terms of their layered structure and A and X elements. However, LAX materials incorporate late transition metals in place of the early transition metals. Advanced techniques for predicting the crystal structure of materials, coupled with data‐driven materials research and machine learning algorithms, were employed to investigate the stable structures containing transition metals from the last groups of the d‐block elements. The analyses revealed 207 ternary LAX systems that demonstrate robust stability against decomposition, with 100 of these systems showing dynamic stability. An in‐depth examination of the top 10 structures revealed five LAX systems that are phase stable and exhibit superior mechanical properties, outperforming MAX phase counterparts in Young's modulus, stiffness, and hardness. These findings indicate that many LAX phase structures are viable candidates for future synthesis, highlighting the potential of heuristic‐based structure searches in material discovery. This research presents LAX phases, innovative layered materials from late transition metals, as alternatives to MAX phases. Using crystal structure prediction and machine learning, we identified 207 stable LAX systems with superior mechanical properties. These findings open pathways for LXene synthesis, promising advancements in catalysis and materials innovation, and highlight the vital role of scientific exploration in shaping a sustainable future.