基于1,4-萘二膦酸钴化合物的合成、晶体结构及磁性质

Cobalt Phosphonates Based on 1,4-Naphthalenediphosphonic Acid:Synthesis,Structure and Magnetic Properties

采用水热法合成了基于1,4-萘二膦酸的新颖钴化合物:[Co_(4)(1,4-ndpaH)_(2)(1,4-ndpaH_(2))(1,4-ndpa)](1,3-dpp)_(2)·6H_(2)O(1)(1,4-ndpaH_(4)=1,4-萘二膦酸,1,3-dpp=1,3-二(4-吡啶)丙烷)。并通过单晶X-射线衍射、元素分析、红外光谱、粉末X-射线衍射及热重分析表征了化合物的结构和热稳定性。单晶结构分析表明,化合物1具有三维开放骨架结构,其中包含有一维孔道,孔道壁由萘环连接共用顶点的四面体{CoO_(4)}和{PO_(3)C}所组成,辅助配体1,3-二(4-吡啶)丙烷未参与配位,填充在一维孔道中,并和结晶水分子产生氢键作用,再通过范德华分子间作用力固定于三维骨架中。化合物1的磁性研究表明Co^(Ⅱ)离子之间存在反铁磁相互作用。

A new cobalt phosphate based on 1,4-naphthalene diphosphonic acid was synthesized by hydrothermal method:[Co_(4)(1,4-ndpaH)_(2)(1,4-ndpaH_(2))(1,4-ndpa)](1,3-dpp)_(2)·6H_(2)O(1)(1,4-ndpaH_(4)=1,4-naphthalene diphosphonic acid,1,3-dpp=1,3-bis(4-pyridyl)propane).The crystal structure and thermal stability of compound 1 was characterized by single crystal X-ray diffraction,elemental analysis,infrared spectroscopy,powder X-ray diffraction and thermogravimetric analysis.Single crystal structure analysis showed that compound 1 had a three-dimensional open framework structure,which contained a one-dimensional channel.The channel wall was composed of corner-sharing{CoO_(4)}and{PO_(3)C}tetrahedra connected by naphthalene rings.The auxiliary ligand 1,3-bis(4-pyridyl)propane fields in the one-dimensional channel without participating in coordination,and formed hydrogen bond with lattice water molecules.The van der Waals intermolecular forces were fixed in the three-dimensional skeleton.Magnetic studies of compound 1 indicated that antiferromagnetic interactions exist between Co^(Ⅱ)ions.