Crystal structure of Mg pivalate hydrate Mg(H2O)6(Piv)2 · 3H2O

Abstract

Single crystals of Mg pivalate hydrate, Mg(H2O)6(Piv)2 · 3H2O (HPiv = (CH3)3CCOOH) are synthesized and their structure is determined by X-ray diffraction method. The crystals are rhombic: a = 10.917(2) A, b = 12.625(2) A, c = 31.394(8) A, Z = 8, space group Pbca, R1 = 0.0525. The Mg atom has octahedral surrounding of the O atoms of water molecules (Mg-O 2.044–2.137 A). The cationic chains of [Mg(H2O)6]∞2+ lie in the voids of doubled network anionic layers of [(H2O)3(Piv)2]∞∞2−. Inside the layer, the pivalate anions alternate with water molecules in the xy plane, being bonded to them by hydrogen bonds. The cationic chains and the anionic layers are united into layered packs by hydrogen bonds between coordinated water molecules and pivalate anions and between coordinated and crystal hydrate water molecules.