Hydrothermal syntheses and crystal structures of two-dimensional (2D) layered vanadium oxide complexes: M(bipy)(H2O)V2O6 (M = Ni, Co, bipy = bipyridine) and [Ni(bipy)2V6O17]

Abstract

Double layered vanadium oxide metal coordination complexes, [Ni(bipy)(H₂O)V₂O₆]_∞1 and {[Ni(bipy)₂]₂V₆O₁₇}_∞2, have been isolated from the same hydrothermal reaction container. X-Ray crystallography shows that 1 consists of unique two-dimensional layers constructed from a vanadium oxide chain {V₂O₆}²ⁿ⁻_n and covalently linked by Ni(bipy)(H₂O)²⁺ subunits. In contrast 2 and the previously reported Zn(bipy)₂V₆O₁₇ are isomorphic compounds. Only [Co(bipy)(H₂O)V₂O₆]_∞, 3, was obtained when cobalt was substituted for nickel in a similar reaction, and X-ray diffraction analysis reveals that the topology of 3 is essentially identical to that of 1. The magnetic behavior of 1 and 2 suggests a dominant single ion effect with only very weak magnetic interactions.