Two synthetic routes generate two isopolyoxoniobates based on {Nb16} and {Nb20}

Abstract

Self-assembly reactions of the Lindqvist-ion salt K₇HNb₆O₁₉·13H₂O, SeO₂, and [Cu(2,2′-bipy)]²⁺ give, depending on different routes, two isopolyoxoniobates based on {Nb₁₆} and {Nb₂₀}, respectively, which, as new members of the very limited isopolyoxoniobate family, are observed for the first time. Furthermore, the solution behavior was investigated to determine the stability of the {Nb₁₆} cluster in water.