Erbium acetylacetonate

Erbium acetylacetonate is a coordination compound with the formula Er(C5H7O2)3. This anhydrous acetylacetonate complex is often discussed but unlikely to exist per se. The 8-coordinated dihydrate Er(C5H7O2)3(H2O)2 is a more plausible formula based on the behavior of other lanthanide acetylacetonates. The dihydrate has been characterized by X-ray crystallography.

Upon heating under vacuum, the dihydrate converts to the oxo-cluster Er4O(C5H7O2)10. This behavior, which is also observed for other lanthanide acetylacetonates, further illustrates the implausibility of six-coordinate Er(C5H7O2)3.