A coordination polymer,namely [Ni(cpna)(bpy)(H2O)]n (1) has been constructed hydrothermally using H2cpna (H2cpna=5-(2′-carboxylphenyl) nicotic acid),bpy (bpy=2,2′-bipyridine) and Ni(OAc)2·4H2O.The complex crystallizes in the monoclinic system,space group P21/c with a=1.666(2) nm,b=0.962 2(12) nm,c=1.2702(16)nm,β=105.978(12)°,V=1.957(4) nm3,Dc=1.608g·cm-3,Z=4,R=0.038 7 and wR=0.089 3 (I＞2σ(Ⅰ)).Three Ni(Ⅱ) atoms,three cpna ligands,three 2,2′-bpy ligands,and three water ligands form a [Ni3(cpna)3(bpy)3(H2O)3] ring.The rings are connected by the coordination interactions of cpna ligands and Ni(Ⅱ) ions to generate a 2D sheet,which are further extended into a 3D metal-organic supramolecular framework by π-π stacking interactions.Magnetic studies for complex 1 show a weak antiferromagnetic coupling between the nearest Ni(Ⅱ) centers,with g=2.10 and J=-0.87 cm-1.CCDC:816351.%通过水热方法,采用H2cpna(H2cpna=5-(2′-carboxylphenyl))和bpy(bpy=2,2′-bipyridine)与Ni(OAc)2·4H2O反应,合成了一个具有二维结构的配位聚合物[Ni(cpna)(bpy)(H2O)]n(1),并对其结构和磁性质进行了研究.结构分析结果表明该聚合物的晶体属于单斜晶系,P21/c空间群.3个镍(Ⅱ)离子、3个cpna配体、3个2,2′-bpy配体和3个配位水分子形成了一个[Ni3(cpna)3(bpy)3(H2O)3]环,这些环通过镍(Ⅱ)离子与cpna配体的配位作用形成了一个二维层状结构.层与层之间又通过π-π堆积作用形成了一个三维的配位框架.研究表明,该聚合物中相邻镍(Ⅱ)离子之间存在很弱的反铁磁相互作用.
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