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Updated: Apr 6, 2026
Growth and Electrostatic/chemical Properties of Metal/LaAlO3/SrTiO3 Heterostructures
Published on: February 8, 2018
Crystal Growth, Structures, and Properties of the Complex Borides, LaOs2Al2B and La2Os2AlB2
Daniel E Bugaris1, Fei Han1, Jino Im2,3
1†Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439, United States.
Abstract:
Single crystals of two novel quaternary metal borides, LaOs2Al2B and La2Os2AlB2, have been grown from La/Ni eutectic fluxes. LaOs2Al2B crystallizes in tetragonal space group P4/mmm with the CeCr2Si2C-type structure, and lattice parameters a = 4.2075(6) Å and c = 5.634(1) Å. La2Os2AlB2 exhibits a new crystal structure in monoclinic space group C2/c with lattice parameters a = 16.629(3) Å, b = 6.048(1) Å, c = 10.393(2) Å, and β = 113.96(3)°. Both structures are three-dimensional frameworks with unusual coordination (for solid-state compounds) of the boron atoms by transition metal atoms. The boron atom is square planar in LaOs2Al2B, whereas it exhibits linear and T-shaped geometries in La2Os2AlB2. Electrical resistivity measurements reveal poor metal behavior (ρ300 K ∼ 900 μΩ cm) for La2Os2AlB2, consistent with the electronic band structure calculations, which also predict a metallic character for LaOs2Al2B.
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