Hydrothermal Synthesis And Properties Of Lanthanide Coordination Polymers Of Linear Organic Acids

Lanthanide coordination polymers of linear organic acids are a kind of new multi-functional material with rich structure and excellent performance.They have potential application in catalysis,photoluminescence,magnetism,gas adsorption and the others.In this work,23 lanthanide coordination polymers of linear organic acids were synthesized by lanthanide ions as the central ion,linear organic acid as ligand and 1,10-phenanthroline as auxiliary ligand under hydrothermal conditions.These compounds were characterized by X-ray single crystal diffraction,elemental analysis,FT-IR spectroscopy,UV/Vis spectroscopy and X-ray powder diffraction.The magnets,fluorescence and thermal stabilities of some compounds were studied.1.Lanthanide fumarates: A series of lanthanide fumarates [Sm2(fum)3(H2fum)(H2O)2](1,H2 fum = fumaric acid),[Ln2(fum)3(H2O)4]·3H2O {Ln = Tb(2),Dy(3)} and [Ln2(fum)3(H2O)4] {Ln = Y(4),Ho(5),Er(6),Tm(7)} were prepared by the hydrothermal methods and their structures were classified into three types.The 3-D framework of compound 1 contains a 1-D infinite [Sm–O–Sm]n chain built up from the connection of SmO8(H2O)polyhedra sharing edges via three –COO group bridges of fumarate ligands,which is further constructed into a 3-D network structure with three kinds of fumarate ligands.Compounds 2-3 consist of a 3-D porous framework with 0-D cavities for the accommodation of chair-like hexameric(H2O)6 clusters.Compounds 4-7 have a 3-D network structure remarkably different from those of 1 and 2-3,due to the different coordination numbers for the Ln3+ ions and distinct fumarate ligand bridging patterns.A systematic investigation of seven lanthanide fumarates and reported compounds revealed that the well-known lanthanide contraction has a significant influence on the formation of lanthanide fumarates.The magnetic properties of compounds 1,3 and 5-7 were also investigated.2.Lanthanide adipates: A series of lanthanide adipates [Ln2(ad)3(H2O)4][Ln = Y3+(8),Ho3+(9),Er3+(10),Tm3+(11);ad = adipate] have been hydrothermally synthesized.Compounds 8-11 are isostructural and exhibit 2-D polymeric layers constructed by Ln3+ ions bridged via the carboxylate groups of adipate ligands in two binding modes.The photoluminescence properties of both 9 and 11 are investigated.3.Lanthanide glutarates:A series of lanthanide glutarates [Ln(phen)(glu)Cl]n {Ln = Y(12),Tm(13);phen = 1,10-phenanthroline;glu = glutarate},[Ln2(phen)2(glu)3]n {Ln = Ce(14),Tb(15),Ho(16)} and [La2(glu)3(H2O)3]n·5nH2O(17)have been hydrothermally synthesized and their structures were classified into three types.Compounds 12-13 are isostructural and consist of 1-D neutral [Ln(phen)(glu)Cl]n chains,which are built up from the linkages of [Ln(phen)Cl]3+ ions and glutarate ligands.Compounds 14-16 are isostructural and contain 2-D [Ln2(phen)2(glu)3]n layers,where Ln3+ ions are connected by three kinds of glutarate ligands.The 3-D framework of compound 17 is constructed by the linkages of La3+ions and glutarate ligands.Compound 17 shows a new structural type.A systematic investigation of six lanthanide glutarates and some reported compounds revealed that the well-known lanthanide contraction has a significant influence on the formation of lanthanide glutarates.The photoluminescent and magnetic properties of some compounds have been studied.4.Organic germanium lanthanide coordination polymers:A series of organic germanium lanthanide coordination polymers [Ln8(phen)2Ge12(μ3-O)24T12-(H2O)16]·2H2O [Ln = Dy(18),Er(19);T=-CH2CH2COO-group,phen = 1,10-phenanthroline],[Ln8(phen)2Ge12(μ3-O)24T12(H2O)16]·2phen·16H2O [Ln = Sm(20),Eu(21),Gd(22)],and [Ho8(phen)2Ge12(μ3-O)24T12(H2O)14]·2phen·13H2O(23)have been hydrothermally synthesized from the reactions of organic germanium and Ln2O3 with auxiliary phen chromophores.Compounds 18-19 consist of cage clusters [Ln8(phen)2Ge12(μ3-O)24T12(H2O)16] and free H2 O molecules,where cage clusters are arranged in a CsCl type,while compounds 20-22 consist of cage clusters [Ln8(phen)2Ge12(μ3-O)24T12(H2O)16],free phen and free H2 O molecules,where cage clusters are arranged in a NaCl type.Compound 23 consists of one-dimensional(1-D)neutral chain [Ho8(phen)2Ge12(μ3-O)24T12(H2O)14]n,free phen and free H2 O molecules.Compounds 18-23 provide rare examples of p–f heterometallic oxoclusters decorated by phen chromophores.