Fig. 2. Luminescence spectra (a) uncomplexed Eu3þ (2.0 103 M) in water,
λex ¼ 394 nm; (b) Eu3þ (1 105 M)–BA (5 104 M) at pH 6.0 in water, λex ¼
277 nm; (c) Eu3þ (1 105 M)–BA (5 104 M) at pH 4.5 in MeCN, λex ¼ 277 nm.
The excitation wavelength used to record each of the spectra is shown alongside.
Table 1