Lanthanum gallium bismuthide, LaGaBi2.
The ternary rare-earth gallium bismuthide LaGaBi(2) has been prepared through reaction of the elements. Its structure (Pearson symbol hP24, hexagonal, space group P6/mmm, Z = 6, a = 13.5483(4) A, c = 4.3937(1) A) contains columns of La(6) trigonal prisms centered by Bi atoms. These columns are surrounded by a framework consisting of three-atom-wide Bi ribbons and Ga(6) rings. Additional Bi atoms are sandwiched between pairs of Ga(6) rings. LaGaBi(2) is structurally closely related to La(13)Ga(8)Sb(21). A retrotheoretical analysis of the structure through extended Hückel band structure calculations suggests an interesting electronic situation in which strong multiple bonding in the Ga-Ga network coexists with weak hypervalent bonding in the Bi-Bi network and confirms the metallic behavior seen in electrical resistivity measurements.
Morgan
Mark G
MG
Department of Chemistry, University of Alberta, Edmonton, Canada T6G 2G2.
Wang
Meitian
M
Chan
Wing Yan
WY
Mar
Arthur
A