A Novel Basic Copper Succinate: Crystal Structure of Diaqua-tetracopper Tetrahydroxyl Disuccinate Trihydrate, [Cu_4 (H_2O)_2 (OH)_4 (C_4H_4O_4)_2]· 3H_2O

[Cu_4 (H_2O)_2 (OH)_4 (C_4H_4O_4)_2]·3H_2O crystallizes in the triclinic space group P 1 (no. 2) with cell dimensions: a = 9.730(2) A, b = 10.605(2) A, c = 12.581 (3) A,a= 111.40(3) °, β = 105.96(3)°, γ = 96.20(3) °, V = 1130.2(4) A~3, D_x = 1.941 g/ cm~3, F(000) = 660, M = 660.43, μ (Mo K_a) = 36.79 cm~(-1), Z = 2, T = 293 K and final R(F_o) = 0.062 and wR(F_o~2) = 0.151 for 3935 reflections (F_o~2 ≥ 2σ (F_o~2)). The basic building blocks in the crystal structure are the distorted polyhedra, i. e., octahedral CuO_6 and square pyramidal CuO_5. The octahedra share common edges with neighbours to form one-dimensional polymeric chains parallel to [100] and three comers of three adjacent CuO_6 octahedra constitute the trigonal face of each square Pyramid. The succinate (C_4H_4O_4) _(2-) ions interlink the polymeric chains to 3-dimensional network with water molecules distributed in the tunnels. The central Cu atom in the octahedral CuO_6 is bonded to one water oxygen, four hydroxyl oxygen and one succinate oxygen with water and hydroxyl oxygens at axial positions (hasal d(Cu-O)= 1.927-- 2.011 A, axial d(Cu-O) = 2.400 - 2.465 A), while the central metal atom in the square pyramidal CuO_5 is coordinated by two hydroxyl oxygens and three oxygens of different (C_4H_4O_4)_ (2-) groups with one apical carboxylate oxygen (hasal d(Cu-O) = 1.944-- 1.980 A, axial d(Cu-O) = 2.365 and 2.410 A). The succinate chains with all C backbone atoms coplanar are tilted to meet one-dimensional close-packing of the polymeric chains and the terminal carboxyl groups are rotated to different extents against the C backbone plane (d(C-O) = 1 .23-- 1 .28 A terminal d(C-C) = 1.51 -- 1.52 A, central d (C-C) = 1 .43 -- 1 .54 A).