The system CsCl:Eu2+, Mn2+, OH- has been studied by photoluminescence
techniques. It has been found that there is an energy transfer between
EU2+ and Mn2+, and OH- and Eu2+ and that the OH- ion increases the en
ergy transfer process between Eu2+ and Mn2+ ions. The energy transfer
rate between europium and manganese ions has been estimated to be of t
he order of 5 x 10(8) s(-1). The results point out that the energy tra
nsfer process between these ions occurs when they are forming close pa
irs in the lattice. (C) 1997 Elsevier Science B.V.