Co[HO2C(CH2)3NH(CH2PO3H)2]2: a new canted antiferromagnet

A new cobalt(II) carboxylate-phosphonate, namely, CoHO2C(CH2)3NH(CH2PO3H)2]2, with a layered architecture has been synthesized by hydrothermal reactions. The Co(II) ion in the title compound is octahedrally coordinated by six phosphonate oxygen atoms from four carboxylate phosphonate ligands. Neighboring CoO6 octahedra are interconnected by phosphonate groups into a 2D layer with a 4,4-net topology. Adjacent layers are further cross-linked via hydrogen bonds between the noncoordinate carboxylate groups and noncoordinate phosphonate oxygens. The ac and dc magnetic susceptibility and magnetization measurements indicate that CoHO2C(CH2) 3NH(CH2PO3H)2]2 is a canted antiferromagnet with T(c) = 8.75 K.