Hydrothermal synthesis and crystal structure of the first layered iron molybdate KH3FeII2MoVI2O10

The layered iron molybdate compound, KH3FeII2MoVI2O10, has been hydrothermally synthesized and structurally characterized for the first time. The compound crystallizes in monoclinic space group C2/m with a=9.6448(7), b=6.5946(4), c=7.8563(5) Å, β=115.950(1)°, V=449.31(5) Å3, Z=2, and R1=0.0313, wR2=0.0817. The structure consists of FeO6 octahedra and MoO4 tetrahedra. Each FeO6 octahedron shares edges with its adjacent FeO6 octahedra and leads to a chain consisting of edge-sharing FeO6 octahedron. The parallel chains are linked through MoO4 tetrahedra. Each MoO4 tetrahedron shares corners with two adjacent Fe octahedra through the vertical oxygen atoms of each FeO6, and two adjacent Fe octahedra through an oxygen atom bridging the two adjacent Fe octahedra of its neighboring chain, respectively. A ∞-like 2D layers and pseudo-six-side tunnels are formed and the potassium cations are located in the pseudo-channels.