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A series of isostructural d/f molecular compounds Zn(H_2L)Ln(NO_3)_3·CH_3OH(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(H_4L = C_(44)H_(60)N_4O_8). 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.
A series of isostructural d / f molecular compounds Zn (H_2L) Ln (NO_3) _3 · CH_3OH (Ln = Dy (1), Tb (2) and Sm N ?, N ??, N ?? - tetra (2-hydroxy-3-methoxy-5-methylbenzyl) -1,4,7,10-tetraazacyclododecan (H_4L = C_ (44) H_ (60) N_4O_8). 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. 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 th ree 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.