Synthesis And Properties Of Multidimensional Rare-earth Carboxylate Coordinated Complexes

Metal-organic fameworks (MOFs) constructed with proper metal ions and ligands have attracted much attention due to their fascinating structures and special function and it has been one of most interesting topics in coordination chemistry, super molecule chemistry and material chemistry. The structural controllability of rare-earth organic coordination complexes is still a great chanllege, not only for the reaction environment such as temperature, ratio, pH and so on, but also for their nature with large radius, high coordinated number, flexible coordination environment.In this paper, in order to get complexes with the functions of optical property and magnetism performance. We chose different carboxylic ligands to coordinate with rare-earth ions, on the basis of that, introducing various auxiliary ligands and transitional metal manganese ion, obtained re-organic complexes from low to high dimension. We also study on the influence on the structures and properties.1. Six re-organic complexes were obtained by introducing 4,4'-bipy,2,2'-bipy and 1,10-phen as auxiliary ligands in the reaction of rare-earth ions and quinoline-2-carboxylic acid under hydrothermal condition. The result indicates that auxiliary ligands have influenced the structure and six complexes have received, of which 1-4 are dinuclear complexes [Ln2(QUIN)6(H2O)6]·3H2O (Ln= Pr (1), Nd (2), Sm (3), Eu (4)), [Pr(QUIN)3(H2O)]n (5) with chain structure and phen participated the coordination to form the dinucler complex [Pr2(QUIN)4(phen)2(NO3)2(H2O)2] (6). The dinuclear structures in 1-4 are further linked together by the hydrogen bond interactions resulting in the formation of the two-dimensional supramolecular network, while the dinuclear structures in 6 form the three-dimensional supramolecular network. Complex 5 is composed of one-dimensional chain framework, which further pack into the two-dimensional layer through weakπ…πstacking interactions. The characters of the complexes have been studied,4 and 6 can emit red and green flourescence, and 2,6 also show antiferromagnetic interaction between the Ln3+ ions, which indicate that they can be made into functional materials.2. Multicarboxylic acid 5-hydroxyisophthalic acid is chosen to coordinate with Y3+ and one-dimensional chain complex [Y(OBDC)(H2O)5](H2O)2(CH3COO) (7) has achieved under hydrothermal condition. On the basis of above work, we introduced 1,10-phen as auxiliary ligand to construct 3-D network Y(OBDC)(phen) (8) with dinuclear secondry building blocks, meanwhile the complex emit green fluorescence.3. Four re-organic complexes were received when 5-nitroisophthalic acid chosen as ligand in hydrothermal reaction,2-D{[Eu(NIPH)(HNIPH)(H2O)2]-2H2O}n (9) is constructed from rod-shaped SBUs and 2-D{[Nd2(NIPH)3(H2O)3]·H2O}n (10) is constructed from tetranuclears building blocks. The result indicates that Mn2+ has impacted the structure of complexes, [Ln2Mn(NIPH)4(H2O)4]·6H2O [Ln=Eu(11), Nd(12)],3-D topological structure is constructed from [Ln2MnO20]-(O-C-O)2-[Ln2MnO20] (Ln=Eu,Nd) heterometallic SUBs, and antiferromagnetic coupled interactions exist in compounds upon decreasing temperature.