Mo(VI)-oxalate derivatives: Thermal behaviour of the |Co(en) 3| 3+ salts of three different oxoanionic complexes

Abstract

Molybdenum(VI) dimeric complexes containing an oxo bridge group are long known. Suggestions on the probable existence of doubly bridged(μ-oxo-μ-hydroxo)dimolybdenum(VI) complex species have been advanced, lacking direct structural confirmation. The study of the thermal behaviour of three different molybdo-oxalate complexes previously described, namely |MoO 2(OH) 2(C 2O 4) 2| 4− and the dimers |Mo 2O 5(OH) 2(C 2O 4) 2| 4− and |Mo 2O 5(OH)(C 2O 4) 2| 3−, has provided evidence regarding the existence of significant structural differences between both dimeric species that support the above hypothesis. On the other hand, a new monomeric trioxo species, |MoO 3(C 2O 4) 2| 4−, has been identified and characterized.