Crystal and molecular structure of bis(aminomethylphosphonate)copper(II)

The crystal and molecular structure of bis(aminomethylphosphonate)-copper(II), C₂H₁₀N₂O₆P₂Cu, has been determined from MoK diffractometer data. The compound crystallizes in the monoclinic space groupP2₁/n witha =7.571(2),b = 4.943(1),c = 11.212(3) Å, = 105.84(2) °, andZ = 2. The structure was solved by the heavy-atom technique and refined by full-matrix least-squares methods toR = 0.041, using 1084 reflections for which ¦F_o¦ > 3.92 (¦F_o¦). In this complex, the Cu atom is square-planar coordinated by four O atoms from four phosphonic groups, and not by the amino group. The Cu-O bond lengths are 1.928(3) and 1.937(3) Å, and the phosphonic groups bridge adjacent Cu atoms in polymeric chains. The infrared spectrum of this complex is reported.