Two novel glycine metal halogenides: catena-poly[[[diaquanickel(II)]-di-mu-glycine] dibromide] and catena-poly[[[tetraaquamagnesium(II)]-mu-glycine] dichloride].

In catena-poly[[[diaquanickel(II)]-di-mu-glycine] dibromide], {[Ni(C2H5NO2)2(H2O)2]Br2}n, (I), the Ni atom is located on an inversion centre. In catena-poly[[[tetraaquamagnesium(II)]-mu-glycine] dichloride], {[Mg(C2H5NO2)(H2O)4]Cl2}n, (II), the Mg atom and the non-H atoms of the glycine molecule are located on a mirror plane. All other atoms are located on general positions. The atomic arrangements of both compounds are characterized by [MO6] octahedra (M=Ni or Mg) connected by glycine molecules, with the halogenide ions in the interstices. In (I), four of the coordinating O atoms are from glycine and two are from water molecules, building layers of octahedra and organic molecules. In (II), two of the coordinating O atoms are from glycine and four are from water molecules. The octahedra and organic molecules form chains.