Lanthanide ions 592 LUMINESCENCE

Horrocks, William DeW., Jr. and Albin, Michael, Lanthanide Ion Luminescence... 

Fig. 7.37. Plots of lanthanide ion luminescence decay constants, k (ms 1), vs. mole fraction of H2O (/h->o) ln HtO-DtO mixtures for Eu(III) and Tb(III). The number of coordinated H20 s, n, for the indicated complexes is given on the right-hand ordinates aquo ions ( ) NTA complexes (pH 6.0) (O) EDTA (1 1) complexes (pH 6.0) (V) EDTA (2 1) complexes (pH 7.5) (A) 11231.

From the lifetimes of the excited states of dilute solutions of Eu3+ and Tb3+ in H2O and D2O the number of coordinated water molecules can be obtained. A typical plot of the lanthanide ion luminescence decay constant against mole fraction of water in H2O-D2O mixtures is shown in Fig. 7.37. The observed decay constant, k0bs is comprised of... 

Topics which have formed the subjects of reviews this year include photosubstitution reactions of transition-metal complexes, redox photochemistry of mononuclear and polynuclear" complexes in solution, excited-state electron transfer processes, transition-metal complexes as mediators in photochemical and chemiluminescence reactions, lanthanide ion luminescence in coordination chemistry, inorganic photosensitive materials," and photocatalytic systems using light-sensitive co-ordination compounds. Reviews have also appeared on the photoreduction of water.Finally, various aspects of inorganic photochemistry have been reviewed in a single issue of the Journal of Chemical Education. 

The unique luminescent properties of rare earth metal clathrochelates have been used in the development of luminescent materials (luminophores and laser materials). The luminescence of these clathrochelates in solution makes their application as biological probes and concentrators of the luminescence (i.e., the antenna effect ) promising. These complexes can also serve as efficient molecular devices to convert UV light absorbed by the ligand to lanthanide ion luminescence in the visible region. Even in very dilute (10-5 mol l-i) solutions, the conversion of irradiated photons to luminescent ones has been observed to occur at a rate of approximately 1%. For rare earth metal aqua ions at the same concentration, the efficiency of conversion is equal to 4 x IQ- % [212, 390-392]. 

Lanthanide ion luminescence in coordination chemistry and biochemistry. W. De W. Horrocks and M. Albin, Prog. Inorg. Chem., 1984, 31,1-104 (432). 

Hope, Hakon, X-Ray Crystallography A Fast, First-Resort Analytical Tool. . Horrocks, William DeW., Jr. and Albin, Michael, Lanthanide Ion Luminescence... 

Horrocks WdeW Jr, Sudnick DR (1981) Lanthanide ion luminescence probes of the structure of biological macromolecules. Ace Chem Res 14 384-392... 

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