Influence of 2-aminopyridine on the formation of molybdates under hydrothermal conditions

Abstract

The hydrothermal reaction of an aqueous ammonium heptamolybdate solution with first-row transition metal salts in the presence of 2-aminopyridine at around 180 °C and under autogenous pressure yields several molybdates, such as the 1D chains in (C5N2H7)4Mo8O26 (1), zero-dimensional (C5N2H7)6Mo7O24·3H2O (2), and the first synthesis of Lindgrenite [Cu3Mo2O8(OH)2 (3)] The structures of these materials were established by single-crystal and powder X-ray diffraction techniques. The crystal structures of wolframite-based MnMoO4 (4) and ZnMoO4 (5) were established by powder X-ray diffraction. The role of 2-aminopyridine (2-ampy) in the formation of the different solids under hydrothermal conditions is discussed.