Hydroxide flux synthesis and crystal structure of the ordered palladate, LuNaPd6O8

We report the single crystal structure of LuNaPd₆O₈ grown from a sodium hydroxide flux. The utilization of a hydroxide flux has led to the preparation of the first ordered substitution of a lanthanide metal and an alkali metal on the A-site in a platinum group oxide and the first palladate to contain both a lanthanide metal and an alkali metal. The 1:1 ordered substitution of Lu³⁺ and Na⁺ in place of the commonly observed divalent cation leads to slabs of LuO₈ and NaO₈ cubes bridged together by PdO₄ square planes. The compound crystallizes in the cubic space group Pm-3 (#200) with a=5.72500(10) Å and is structurally related to other cubic palladium oxides.