Crystal and electronic structures of La2LiGe6−x (x = 0.21) and La2LiGe4Si2
Abstract:The synthesis and characterization of a new ternary dilanthanum lithium hexagermanide, La2LiGe6−x (x = 0.21), belonging to the Pr2LiGe6 structure type, and a quaternary dilanthanum lithium tetragermanium disilicide, La2LiGe4Si2, which crystallizes as an ordered variant of this type, are reported. In both structures, Li is on a site of mmm symmetry. All other atoms are on sites of m2m symmetry. These structures are new representatives of a homologous linear structure series based on structural fragments of the AlB2, CaF2 and ZrSi2 structure types. The observed 17‐vertex polyhedra are typical for La atoms and the environment of the Li atom is cubic. Two Ge atoms are enclosed in a tetragonal prism with one added atom (nine‐vertex polyhedron). The trigonal prismatic coordination is typical for Ge or Si atoms. The metallic nature of the bonding is indicated by the interatomic distances and electronic structure calculations.
Document Type: Research Article
Publication date: August 15, 2012