The mechanism of energy transfer in the diphosphate CsY1-xGdxP2O7 (0 <
x less than or equal to 1) has been studied both at room and at liqui
d nitrogen temperatures. Decay curves of the emission arising from the
P-6(7/2) state of Gd3+ were analyzed in the entire concentration rang
e. The experimental curves have been fitted with the Yokota and Tanimo
to model, assuming a diffusion-limited process. The derived diffusion
constant and interaction parameters suggest a temperature dependence o
f this process. (C) 1998 Elsevier Science Ltd.