Disodium diaquabis(methylenediphosphonato-κ2O,O′)cobaltate(II) dihydrate

Abstract

In the title compound, Na2[Co(CH4O6P2)2(H2O)2]·2H2O, the asymmetric unit is composed of one methylenediphosphonate ligand and one water molecule, which both are coordinated to a CoII atom, as well as a non-coordinated water molecule and a sodium cation. The CoII atom occupies a special position on a crystallographic inversion centre. The slightly distorted CoIIO6 octahedral coordination environment is composed of two bidentate methylenediphosphonate ligands and two coordinated water molecules in trans positions. The sodium ion is octahedrally coordinated to six O atoms with Na—O distances ranging from 2.3149 (12) to 2.6243 (12) Å. An extensive three-dimensional network of intermolecular as well as intramolecular O—H...O and C—H...O hydrogen bonding interacions is present.