Construction And Properties Of Rare Earth Complexes Based On Chiral Schiff Base Or Naphthalene Carboxylic Acid Ligands

Rare earth organic complexes have become one of the hot spots in functional material science for their important application in the fields including optical,electrical and magnetic material due to the specific 4f electronic structure.The main contents in this paper include two aspects: One is the synthesis of the chiral 3d-4f magnetic and luminescent complexes by the introduction of chiral structure and transition metal zinc???in Salen type schiff base and sensitizing luminescent lanthanide ions through d-f energy transfer.Another is the utilizing of multi-naphthalene carboxylic acid due to the flexible carboxylic acid ligand coordination modes.Functional complexes were fabricated through the reaction between multi-naphthalene carboxylic acid and rare earth ions,which have potential application of magnetic material and the adsorbent material.A lot of characterization methods were adopted,including X-ray single-crystal diffraction,IR spectroscopy,Uv-vis spectrum,fluorescence spectrum,circular dichroism?CD?spectroscopy,single crystal powder diffraction and N₂ adsorption-desorption.The structure of complexes and magnetism are analyzed in detail.The main results are as follows:1.The precursor building blocks were obtained utilizing chiral salen schiff base coordinated with transition metal Zn???,Then reactions were carried out with rare earth ions through precursor building blocks.Twenty heterometallic dinuclear complex were obtained through thermostat volatile solution method,[Zn?CH₃CN??L'?Ln?NO₃?₃]?Ln=Sm?1R,6S?,Eu?2R,7S?,Gd?3R,8S?,Tb?4R,9S?,Dy?5R,10S??and [Zn?CH₃CN??L"?Ln?NO₃?₃]?Ln=Sm?11R,16S?,Eu?12R,17S?,Gd?13R,18S?,Tb?14R,19S?,Dy?15R,20S??.The single-crystal X-ray diffraction analysis indicated that the complexes have same crystal structure,monoclinic crystal system,P21 space group.Fluorescence spectra show that complexes 1,4,5,11 and 14 rare earth ions exhibit characteristic emission peaks.Magnetic test research show that complexes 3-5,13-15 exist antiferromagnetic coupling between Ln???ion,4,5,14 and 15 complexes present anisotropy,15 complexes exist slow magnetic relaxation phenomena.2.The multiple carboxylic acid 1,4,5,8-naphthalene tetracarboxylic acid were choosen as ligand,three complexes with three dimensional strucures have been obtained under hydrothermal conditions,[Ln?L?Na₂?H₂O?₄?OH?]n(L=Naphthalene-1,4,5,8-tetracarboxylicacid,?Ln=Gd?21?,Tb?22?,Dy?23??.The single-crystal X-ray diffraction analysis indicated that the complexes have same crystal structure,orthogonal crystal system,Cmca space group.Gas adsorption-desorption test indicate coordination polymersisotherms 22 is similar to the ?types isotherm,Magnetic tests indicate the presence of antiferromagnetic coupling Complex21,22-23 are ferromagnetic,Ac susceptibility tests showed that coordination polymers 22 having a field-induced slow magnetic relaxation behavior.