Crystal Structure and Electrical Properties of New Triple Molybdate Na0.45K1.55Cu3(MoO4)4

Abstract

Single crystals of new triple molybdate - sodium potassium copper(II) tetra-[molybdate(VI)] Na_0.45K_1.55Cu₃(MoO₄)₄ - are synthesized by a solid-state reaction and its crystal structure is determined. The compound crystallizes in the monoclinic space group P2₁/c with a = 5.097(2) Å, b = 14.594(3) Å, c = 19.905(3) Å, β = 94.00(2)°, V = 1476.9(7) ų, Z = 4. K2 and Na1 cations are located at the same general site with occupancies of 0.55 and 0.45 respectively. The structure is formed by infinite Cu₃Mo₃O₂₃-type ribbons. These ribbons are connected by a tridentate tetrahedron sharing vertices to build layers parallel to the (001) plane. All these layers are connected by vertices to form a three-dimensional framework. The structural model is supported by the bond valence sum. The electrical properties of the title compound are investigated using complex impedance spectroscopy.