Strontium D-glutamate Hexahydrate and Strontium Di(hydrogen L-glutamate) Pentahydrate

[Sr(C5H7NO4)].6H2O, (I), and [Sr(C5H8NO4)2].5H2O, (II), both crystallize with similar strontium-glutamate-water layers. In (I), the neutral layers are connected through hydrogen bonds by water molecules, while in (II), the positively charged layers are connected through hydrogen bonds and electrostatic interactions by interleaving layers of hydrogen glutamate anions and water molecules.