  The effect of introducing a relay dye on the energy transfer efficiency in a
new donor-acceptor system has been studied. The values of the critical transfer
distance, the reduced concentration, and the energy transfer efficiency of the
cascaded system (consisting of three dyes- donor-relay dye-acceptor) are
compared with that of the two dye system. Experimentally, it has been observed
that the presence of a relay dye increases the transfer efficiency from the
donor to the acceptor.
