Metal monophosphonates M{(2-C5H4NO)CH2PO3}(H2O)2 (M = Co, Ni, Mn, Cd): synthesis, structure, and magnetism.

Four isostructural metal monophosphonates, M{(2-C(5)H(4)NO)CH(2)PO(3)}(H(2)O)(2) with M = Co (1), Ni (2), Mn (3), and Cd (4), were synthesized and structurally characterized. These compounds show a double-chain structure in which the M(2)(μ-O)(2) dimers are connected by O-P-O bridges. The magnetic responses of 1-3 were investigated over a wide range of magnetic fields (up to 10 T) and temperatures (down to 50 mK).