The synthesis of nonclassical polyhedra is at the forefront of supramolecular research because of their unique anisotropic interior cavities.However,due to the difficulty in controlling the topology of Ln supramolecul...The synthesis of nonclassical polyhedra is at the forefront of supramolecular research because of their unique anisotropic interior cavities.However,due to the difficulty in controlling the topology of Ln supramolecular systems,the preparation of nonclassical lanthanide organic polyhedrals(LOPs)remains a challenge.Herein,we explore the ionic radius-dependent self-assembly of LOPs using a rectangular tetratropic ligand L.Owing to the rectangular geometry of the ligand panels(rather than square),its assembly with lanthanide ions located in the middle of the Ln series afforded an irregular tetragonal antiprismatic Ln_(8)L_(4)(Ln=Sm^(3+),Eu^(3+),Tb^(3+),Dy^(3+)and Ho^(3+))with two faces unoccupied with L ligands.Interestingly,this tetragonal antiprism possessed an oblate internal cavity that binds to four THF molecules in the solidstate structure.With an increase in radius,the larger La^(3+)and Nd^(3+)ions produced Ln_(4)L_(2) with a distinct sandwich square architecture.In contrast,the smaller Er^(3+)and Lu^(3+)ions gave rise to a mixture of both Ln_(8)L_(4) and Ln_(6)L_(3).On adding excess Ln^(3+)ions,a structural transformation from Ln_(8)L_(4) to Ln_(6)L_(3) occurred.Structural comparisons of La_(4)L_(2) and Sm_(8)L_(4) revealed that the differences in architecture within these systems were governed by both the ionic radii of the lanthanides and conformational flexibility of the ligands.Photophysical investigations revealed that the ligand L exhibited a sensitizing ability toward Sm^(3+),Tb^(3+)and Dy^(3+)ions,displaying their characteristic luminescence emission,with a new record-setting luminescent quantum yield of 92.74%observed for Tb_(8)L_(4).This work provides new insights into the effect of lanthanide size on the resulting assemblies and opens new avenues to develop nonclassical LOPs.展开更多
基金supported by the National Natural Science Foundation of China(No.22171264)the Science Foundation of the Fujian Province(No.2022J01507)the Self-deployment Project Research Program of Haixi Institutes,Chinese Academy of Sciences(CXZX-2022-GH01).
文摘The synthesis of nonclassical polyhedra is at the forefront of supramolecular research because of their unique anisotropic interior cavities.However,due to the difficulty in controlling the topology of Ln supramolecular systems,the preparation of nonclassical lanthanide organic polyhedrals(LOPs)remains a challenge.Herein,we explore the ionic radius-dependent self-assembly of LOPs using a rectangular tetratropic ligand L.Owing to the rectangular geometry of the ligand panels(rather than square),its assembly with lanthanide ions located in the middle of the Ln series afforded an irregular tetragonal antiprismatic Ln_(8)L_(4)(Ln=Sm^(3+),Eu^(3+),Tb^(3+),Dy^(3+)and Ho^(3+))with two faces unoccupied with L ligands.Interestingly,this tetragonal antiprism possessed an oblate internal cavity that binds to four THF molecules in the solidstate structure.With an increase in radius,the larger La^(3+)and Nd^(3+)ions produced Ln_(4)L_(2) with a distinct sandwich square architecture.In contrast,the smaller Er^(3+)and Lu^(3+)ions gave rise to a mixture of both Ln_(8)L_(4) and Ln_(6)L_(3).On adding excess Ln^(3+)ions,a structural transformation from Ln_(8)L_(4) to Ln_(6)L_(3) occurred.Structural comparisons of La_(4)L_(2) and Sm_(8)L_(4) revealed that the differences in architecture within these systems were governed by both the ionic radii of the lanthanides and conformational flexibility of the ligands.Photophysical investigations revealed that the ligand L exhibited a sensitizing ability toward Sm^(3+),Tb^(3+)and Dy^(3+)ions,displaying their characteristic luminescence emission,with a new record-setting luminescent quantum yield of 92.74%observed for Tb_(8)L_(4).This work provides new insights into the effect of lanthanide size on the resulting assemblies and opens new avenues to develop nonclassical LOPs.
