Lanthanide ions solvent effects

Reinoso-Garcra, M.M., Verboom, W., Reinhoudt, D.N., Brisach, R, Arnaud-Neu, R, Liger, K. Solvent extraction of actinides and lanthanides by CMP(O)- and N-acyl(thio) urea-tetrafunctionalized cavitands Strong synergistic effect of cobalt bis(dicarbollide) ions. Solvent Extr. Ion Exch. (2005), 23 (3), 425-437. 

It should be pointed out that not all the ions discussed here are affected by the outer fields. In fact, lanthanide ions may be affected by solvents or coordination fields in chemical reactions. For example, E and E will change because of the coordination effect of water or organic molecules in an extraction. In addition, the amount of change would be different in different media. The tetrad effect would thus be different in different systems. The tetrad effect not only relates to the electronic configurations of lanthanide elements but is also affected by the surrounding conditions. Currently it is still not possible to predict the tetrad effect or to calculate it quantitatively. Tetrad effect theory still needs to be improved and further data need to be accumulated. 

The complexes of lanthanide ions with the heavy halides, particularly iodide, are often extremely weak. In many cases preparation of these complexes in or from solution is very difficult if not impossible. The donor properties of any otherwise satisfactory solvent or the donor properties of difficult to remove solvent impurities are such that they effectively compete with the halide ion and prevent its entering the metal coordination sphere. The preparative method discussed here, which is applicable to the preparation of salts of bromo... 

Inorganic phosphors are potential labels for time-resolved luminescence staining and assays in aqueous environment [23, 52-55]. The lanthanide phosphors have essentially infinite shelf life, no toxicity, no photobleaching, and are unaffected by environmental conditions such as pH, temperature, enzymatic reactions, or solvent effects. Their major drawback is that the luminescence per lanthanide ion is significantly less than from the dye-doped or dye nanoparticles due to the weak absorption of individual ions partly compensated by their higher number. Inorganic nanoparticles, however, can be prepared readily in large quantities with relatively simple methods. The size of the nanoparticles can be controlled from low nanometer scale to several hundred nanometers with a narrow size distribution. 

The lifetime data contains a range of different ligand systems, in different solvents, and is only intended as an indication of usually observed values. As will be explained below, the surrounding ligand and solvent have profound effects on the non-radiative deactivation of NIR luminescent lanthanide ions. 

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