The first amorphous and crystalline yttrium lactate: synthesis and structural features.

The synthesis and crystal structure of the first molecular yttrium lactate complex, Y(Lac) 3 (H 2 O) 2 , is reported, where the coordination sphere of yttrium is saturated with lactate ligands and water molecules, resulting in a neutral moiety. In Y(Lac) 3 (H 2 O) 2 , hydrogen bonding between α-hydroxy groups and water molecules allows for the formation of 2D layers. A subtle variation in synthetic conditions, i.e. a slight increase in pH (5.5 instead of 4.5) promoted the formation of a semi-amorphous fibrous material with a presumed chemical composition of Y 4 (OH) 5 (C 3 H 5 O 3 ) 7 ·6H 2 O. The flattened fibres in this material are responsible for its good flexibility and foldability.