Na₁₄K₆Tl₁₈M (M = Mg, Zn, Cd, Hg) and Na_13.5Sm_0.5K₆Tl₁₈Na: Novel Octahedral and Centered Icosahedral Cluster Phases Related to the Mg₂Zn₁₁‐Type Structure

Abstract

The cubic Na14K6TI18M Zintl phases (M = Mg, Zn) are not only derivatives of the Na4K6Tl13 structure, but also isopointal with the Mg2Zn11, Mg2Al5Cu6, and Na2In5Au6 intermetallic compounds. The section of the structure shown on the right depicts the two cation types and the isolated Tl octahedra and Tl12M icosahedra. A wide variety of bonding interactions and tuning prospects are evident.