Gonzales-Lorenzo

Fig. 25. Molecular structure of [Ce(17b)]+, redrawn from (Gonzales-Lorenzo et al., 2003).

The three Schiff-base bibracchial lariat ethers H2l7a-c derivatives have been designed for their ability to form a cryptand-like cavity upon reaction with Lnm ions, the size of which can be tuned by varying the number of -CH2-CH2-O- units in the macrocycle. The two 2-salicylaldiminobenzyl pendant arms fold in such a way that jt-jt interactions between aromatic rings result in the formation of a cryptand-like cavity, as demonstrated by the X-ray structure of the Cem complex with 17b depicted on fig. 25 (Gonzales-Lorenzo et al., 2003). The triplet state of the di-anionic receptor is located at 18750 cm-1 (0-phonon component measured on the Gd111 complex) so that sensitization of the NIR luminescence is not optimum nevertheless, Ndm emission could be detected. 

Complexes for which only lifetimes have been determined Crown ether 17c 337 CH3CN 0.78 (Gonzales-Lorenzo et... 

Gonzales-Lorenzo, M., Platas-Iglesias, C., Avecilla, F., Faulkner, L.R., Pope, S.J.A., de Bias, A., Rodriguez-Blas, T., 2005. Inorg. Chem. 44, 4254. 

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