A series of isostructural d/f molecular compounds Zn(H2L)Ln(NO3)3·CH3OH(Ln = Dy(1), Tb(2) and Sm(3)) were synthesized by the introduction of a designed multifunctional ligand N,N?,N??,N???-tetra...A series of isostructural d/f molecular compounds Zn(H2L)Ln(NO3)3·CH3OH(Ln = Dy(1), Tb(2) and Sm(3)) were synthesized by the introduction of a designed multifunctional ligand N,N?,N??,N???-tetra(2-hydroxy-3-methoxy-5-methylbenzyl)-1,4,7,10-tetraazacyclododecan(H4L = C(44)H(60)N4O8). In the isostructural molecules, each crystallographically independent Zn2+ and Ln3+ centers are connected by two phenolic oxygen atoms. For the six-coordinate Zn-(2+) ion, the coordination geometry can be viewed as a regular bicapped square pyramid. While for the ten-coordinate Ln-(3+) ion, if each O,O?-chelated nitrate ligand is seen as a single coordination site, the coordination geometry can be viewed as a distorted pentagonal bipyramid. The fluorescent spectra show that compounds 2 and 3 exhibited characteristic sharp emissions of Tb-(3+) and Sm-(3+), respectively, while compound 1 was found to be a single-component white-light-emitting complex in the solid state. Thermal stabilities of the three compounds were investigated by using thermal gravimetric analysis. In addition, the thermal decomposition of compound 1 was confirmed by temperature-dependent powder X-ray diffraction technique.展开更多
基金supported by the Natural Science Foundation of China(No.21171165,21201165 and 91122015)
文摘A series of isostructural d/f molecular compounds Zn(H2L)Ln(NO3)3·CH3OH(Ln = Dy(1), Tb(2) and Sm(3)) were synthesized by the introduction of a designed multifunctional ligand N,N?,N??,N???-tetra(2-hydroxy-3-methoxy-5-methylbenzyl)-1,4,7,10-tetraazacyclododecan(H4L = C(44)H(60)N4O8). In the isostructural molecules, each crystallographically independent Zn2+ and Ln3+ centers are connected by two phenolic oxygen atoms. For the six-coordinate Zn-(2+) ion, the coordination geometry can be viewed as a regular bicapped square pyramid. While for the ten-coordinate Ln-(3+) ion, if each O,O?-chelated nitrate ligand is seen as a single coordination site, the coordination geometry can be viewed as a distorted pentagonal bipyramid. The fluorescent spectra show that compounds 2 and 3 exhibited characteristic sharp emissions of Tb-(3+) and Sm-(3+), respectively, while compound 1 was found to be a single-component white-light-emitting complex in the solid state. Thermal stabilities of the three compounds were investigated by using thermal gravimetric analysis. In addition, the thermal decomposition of compound 1 was confirmed by temperature-dependent powder X-ray diffraction technique.