Materials Department, University of California, Santa Barbara, California 93106, USA.
Phys Rev Lett. 2018 Dec 21;121(25):255701. doi: 10.1103/PhysRevLett.121.255701.
Pathways connecting dissimilar crystal structures are fundamental to our understanding of structural phase transitions. In this Letter, we report on a new pathway connecting the hexagonal close-packed crystal structure to a hierarchy of topologically close-packed phases consisting of kagome and triangular nets. Common intermetallic structure prototypes such as the Friauf-Laves phases, CaCu_{5}, Ce_{2}Ni_{7}, Be_{3}Nb, and Co_{7}Gd_{2} are specific members of this hierarchy. We find that the pathway is facile for compounds with large atomic size differences, which has implications for the nucleation mechanism of these complex phases.
连接不同晶体结构的途径对于我们理解结构相变至关重要。在这封信中，我们报告了一种将六方密堆积晶体结构连接到由 kagome 和三角形网组成的拓扑密堆积相层次结构的新途径。常见的金属间化合物结构原型，如 Friauf-Laves 相、CaCu_5、Ce_2Ni_7、Be_3Nb 和 Co_7Gd_2，都是这个层次结构的特定成员。我们发现，对于原子尺寸差异较大的化合物来说，这条途径是很容易的，这对这些复杂相的成核机制有影响。
