| Currently,the development of functional complexes has been a hotspot.As the new functional compounds,metal organic framework materials?MOFs?has many advantages such as large surface area,high porosity,high thermal stability and solvent stability,decorating structure and so on.Therefore,it can be widely used in catalysis,luminescent and magnetic materials,gas storage and biomedical fields.Due to unique electronic shell of lanthanons,lanthanide-based MOFs has diverse structures and properties,so it has become a major project for many disciplines.In this paper,nine new rare earth functional complexes were designed.besides,their catalytic and magnetic properties have been explored,as well as the relationship between structure and properties.The main works as following:1.The characteristics and recent development of MOFs and the application of lanthanide-based metal-organic frameworks in catalysis and magnetic properties have been explained briefly.The significance of this research is also discussed simultaneously.2.Inthiscontribution,twocompounds[Dy2Cu4I4?NA?6?DMF?2]n?1?and[Gd2Cu2I2?IN?6?DMF?4]·5DMF?2??HNA=nicotinic acid,HIN=isonicotinic acid?were successfully synthesized and structurally characterized.They were both composed of multinuclear lanthanide ions and copper iodide clusters?[Cu4I4]for 1 and[Cu2I2]for 2?and display excellent solvent and thermal stability.Interestingly,both of them exhibit highly effective catalytic activity in the cycloaddition reaction of propargylic alcohols at room temperature with atmospheric pressure of CO2,and 1 features higher catalytic activity than that of 2 in this reaction system.3.Five dinuclear centrally symmetric Dy-based complexes were constructed at room temperature with five different solvents?H2O,methanol,ethanol,n-propanol and n-butanol?,naming[Dy2?dbm?2?L1?2?H2O?2]·CH3CN?3?,[Dy2?dbm?3?L1?2?CH3OH?]·CH3OH?4?,[Dy2?dbm?2?L1?2?C2H5OH?2]?5?,[Dy2?dbm?2?L1?2?C3H7OH?2]·?C3H7OH?2?6??[Dy2?dbm?2?L1?2?C4H9OH?2]·CH3CN?7?.Crystal structure and slow magnetic relaxation behaviors measurement showed that all of complexes are single molecule magnets,and the slow magnetic relaxation behaviors can be controlled by changing the local coordination environment of the central ions.4.Two novel tetranuclear Ln?III?complexes,namely[Ln4??3-OH?2?tmhd?4?L2?6]?Ln?III?=Gd?1?,Dy?2?;HL2=5-?2-thenylidene?-8-hydroxylquinoline;tmhd=5-?4-methylbenzylidene?-8-hydroxylquinoline?,were synthesized and their structures and magnetic properties were characterized.Two complexes are both composed of one planar[Ln4??3-OH?2]center,in which adjacent eight-coordinated Ln?III?ions are bridged by phenoxy oxygen atoms and?3-OH molecules.Magnetic investigation revealed that complex 1displays cryogenic magnetic refrigeration properties with-?Sm=21.13 J·kg-1·K-11 at T=2.5 K and?H=7.0 T.For complex 2,slow magnetic relaxation behaviors with energy barrier of67.8 K was observed. |
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