Lanthanide ions quantum yield

Because of the higher sensitivity of Ndm ions towards deactivation through O-H oscillators, the complexes with this lanthanide have much lower quantum yields and lifetimes when compared to Ybm. The best photophysical properties are obtained with phthalexon S and since complexes with PS contain 4-5 water molecules, depending on the lanthanide ion, it is quite clear that exclusion of these water molecules from the first coordination sphere will lead to much enhanced luminescent properties. This is indeed demonstrated by bis(cyclen)-substituted PS, H736 (see fig. 36), which increases quantum yields to 0.23 and 1.45% in D2O for Ndm and Ybm, respectively (Korovin and Rusakova, 2002). 

Pyrazoylborates Tetradentate (86) andhexadentate (87) pyrazoylborates (seefig. 74) form a range of 1 1 and 1 2 complexes with Lnm ions, as well as ternary 1 1 1 adducts with dibenzoylmethanate, which have coordination number between 8 and 12. In the case of visible-emitting lanthanide ions, large quantum yields have been recorded, up to 50% for Tbm for instance (Armaroli et al., 1997). With Ndm and Ybm, four types of complexes... 

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