含有(2-吡啶甲基)胺基甲基膦酸与草酸配体的同构稀土(Gd，Tb)化合物的合成、结构、磁学和荧光性质

利用水热合成手段,(2-吡啶甲基)胺基甲基膦酸、草酸盐与醋酸钆(或醋酸铽)配位组装得到2个同构的稀土化合物Ln2(pmampH)(C2O4)2.5(H2O)3.4H2O(Ln=Gd(1),Tb(2))。在2个化合物中,网状的{Ln2(C2O4)2.5}n层通过{LnO8}多面体与{PO3C}四面体的共角连接,形成三维开放结构。沿b方向,可以观察到一维孔道,它们被未配位的(2-吡啶甲基)胺基以及晶格水分子占据。化合物2在部分或全部脱去结构中的配位以及晶格水以后,可以保持它的骨架结构。磁性研究表明化合物1表现出顺磁行为,2则表现出主要的铁磁性相互作用。化合物2以及它的脱水产物的荧光性质也被测定,都表现出Tb(Ⅲ)的特征发射,能够发出绿光。

Isostructural Lanthanide (Gd, Tb) Oxalatophosphonates with 2-Pyridylmethylamino)methyl Phosphonic Acid: Syntheses, Structures, Magnetic and Fluorescent Properties

Two isostructural lanthanide oxalatophosphonates Ln2(pmampH)(C2O4)2.5(H2O)3.4H2O(Ln=Gd(1),Tb(2)) have been obtained through hydrothermal reactions of(2-pyridylmethylamino)methyl phosphonic acid(pmampH2),oxalate,and Gd/Tb salts.Both compounds exhibit 3D open framework,in which the netlike {Ln2(C2O4)2.5}n layer containing Ln10(C2O4)10 rings are connected through corner-sharing {LnO8} polyhedra and {PO3C} tetrahedra,generating channels along b axis filled with the pendant 2-pyridylmethylamino groups and lattice water molecules.The framework of 2 can be retained after partly or completely releasing coordination and lattice water molecules.The magnetic studies show that the presence of paramagnetic behavior in 1,while dominant ferromagnetic interactions in 2.The solid-state fluorescent measurements reveal that 2 and its dehydration products can emit green light,exhibiting characteristic transitions of Tb(Ⅲ).