Synthesis, crystal structure and characterizations of a novel lanthanide oxalatophosphonate with a 3D open-framework structure [Gd2{HO3PCH2NHCH2(CH2CH2OPO2)}(C2O4)2.5(H2O)2] · 5H2O

A novel lanthanide oxalatophosphonate, [Gd2{HO3PCH2NHCH2(CH2CH2OPO2)}(C2O4)2.5(H2O)2] · 5H2O 1 has been synthesized by hydrothermal reaction at 140 °C and structurally characterized by single-crystal X-ray diffraction as well as with infrared spectroscopy, elemental analysis and thermogravimetric analysis. The interconnection of gadolinium(Ш) ions by bridging H2L– anions leads to a 3D open-framework structure with channels along the a-axis. The channel is formed by 44-membered rings composed of six gadolinium(Ш) ions and six H2L– anions. The chelating and bridging oxalates are found on the surface of the channels extending along the a direction.