Synthesis of [Ni(C_6H_4O_2N)_2(H_2O)_2] and its Crystal Structure

A new nickel complex,[Ni(C6H4O2N)2(H2O)2],where HC6H4O2N was 4-carboxylicpyridine,had been synthesized by the reaction of 4-carboxylicpyridine and nickel acetate under hydrothermal conditions,and the crystal structure had been determined based on single crystal diffraction data.The complex crystallized in triclinic system,space group Pī with a = 6.3070(10)A.,b=6.9310(11)A.,c=9.2770(14)A.;α=96.313(2)°,β = 105.189(2)°,γ=113.359(3)°,V=348.67(9)A.3,Z = 1,Dc = 1.786 g·cm-3,F(000) =194,μ =1.439 mm1,λ(MoKα) = 0.71073A.,Mr=374.98.The final R1=0.0783 and ωR2=0.2055 for 1055 observed reflections with I2σ(Ⅰ),and R1=0.0819 and ωR2=0.2104 for all data,where ω-1=[s2(F0)2+(0.1832P)2+0.0000P],P=(F02+2Fc2)/3.The Ni(Ⅱ) ion adopted a slightly distorted sixcoordinated octahedral geometry with symmetry center by four O atoms from four coordinated water molecules and two N atoms from two 4-carboxylicpyridine ligands.Coterminous molecules packed via many H-bonds between the carboxyls from 4-carboxylicpyridine ligands and the coordinated water molecules to forma three-dimensional network structure.