Assembly of Structural Types of Frank–Kasper Phases Cr3Si, MgCu2 and MgZn2 from a Universal Building Unit

• Published in: Metal science and heat treatment Vol. 62; no. 11-12; pp. 659 - 663
• Main Authors: Talis, A. L., Everstov, A. A., Kraposhin, V. S., Simich-Lafitskii, N. D.
• Format: Journal Article
• Language: English
• Published: New York Springer US 01-03-2021; Springer Nature B.V
• Subjects: Chains; Characterization and Evaluation of Materials; Chemistry and Materials Science; Classical Mechanics; Engineering Thermodynamics; Heat and Mass Transfer; Intermetallic compounds; Liquid metals; Materials Science; Metallic Materials; Phase transitions; Phases; Structural models; Structure; Tetrahedra; crystal structure; tetrablock; linear substructure; universal building unit; structural type; Frank–Kasper phases
• ISSN: 0026-0673; 1573-8973
• DOI: 10.1007/s11041-021-00619-3

An approach to description of the structural types of phases is suggested, in accordance with which the structural types A15, C15 and C14 of Frank–Kasper phases are described as the densest packing of chains of special unions of tetrahedrons-tetrablocks. A tetrablock is a seven-vertex union of four tetrahedrons over faces. For the packing to be the densest, the ideal tetrahedrons in the tetrablocks should undergo a minimum possible deformation. Since a tetrablock is a natural structural unit of one-dimensional chains, the approach developed may be used for plotting structural models of phase transitions where the transformation develops within linear substructures. Chains of tetrablocks may also be structural components of metallic melts and glasses.