Tb3+ [5D4] excited state quenched by La3+

Tb³⁺ [⁵D₄] quenched by La³⁺ at conc. <= 0.1 mol L^–1
Solvent : Acetone, 20ºC

k_q < 2 x 10³(L mol^–1 s^–1)

Mechanism: energy transfer
Experimental methods: conventional flash, luminescence, , luminescence
Lifetime in the absence of quencher, air free = 1100 micro sec.