Hydrogen Bonded Framework Structures Constructed from 2-(Pyridyl <i>N</i>-oxide) Methylphosphonic Acid Ligands and Erbium(III)

Syntheses for 2-(pyridyl N-oxide) methylphosphonic acid, 1-H, and 2-(pyridyl N-oxide) hydroxymethylphosphonic acid, 4-H, are described, and the crystal structures of both ligands are presented. Combination of these ligands with freshly prepared erbium hydroxide results in the formation of the isostructural complexes Er(L-)3(LH)·8H2O. The crystal structure determinations of the complexes show that extensive hydrogen bonding links the individual eight coordinate Er(L-)3(LH) molecular units into a 3-D structure.