Tb3+ [5D3] excited state quenched by Sm3+

Tb³⁺ [⁵D₃] quenched by Sm³⁺ at conc. <= 0.05 mol L^–1
Solvent : POCl₃/SnCl₄ (9/1), 20ºC

k_q = 5.3 x 10⁴(L mol^–1 s^–1)
Activation energy = 23 (–15 to +20ºC)(kJ mol^–1)

Mechanism: energy transfer
Experimental methods: conventional flash, luminescence, single shot signal
Lifetime in the absence of quencher, air free = ~500 micro sec.