Synthesis and Molecular Structure of Tetranuclear Complex Cu_2Ca_2L_2(H_2O)_6·2H_2O

The transition metal and alkaline earth metal tetranuclear complex Cu2Ca2L2(H2O)6·2H2O where H4L represents the Schiff base N-3-carboxylsalicylideneglycylglycine was prepared and its crystal structure was determined by the single-crystal X-ray diffraction method at room temperature. It crystallizes in the monoclinic system, space group C2/c. The lattice parameters are a=2.128 2(2) nm, b=1.231 73(14) nm, c=1.323 42(15) nm, β=93.619(2)°, Mr=939.81, Dc=1.803 Mg·m-3, F(000)=1 928, Z=4 with R1=0.046 6. Each copper atom is coordinated by two nitrogen atoms, one carboxylate oxygen atom and one phenolic oxygen atom, in a square-planner manner. And each calcium atom is coordinated by three water oxygen atoms, three carboxylate oxygen atoms and one phenolic oxygen atom in a distorted pentagonal bipyramid. Two pentagonal bipyramids are connected by two carboxyl groups. CCDC: 239969.