In order to interpret the photoluminescence spectra of spherical nanoc
rystals with zincblende structure, the intensities of phonon satellite
s are analyzed taking into account both the internal non-adiabaticity
of the exciton-phonon system (the proper Jahn-Teller effect) and the e
xternal non-adiabaticity (the pseudo-Jahn-Teller effect). The effects
of nonadiabaticity are shown to lead to a significant enhancement of p
honon-assisted transition probabilities and to a more complicated depe
ndence of these probabilities on the number of emitted or absorbed pho
nons in comparison with the results of adiabatic theory. The calculate
d relative intensities of the phonon satellites compare well with the
experimental data on the photoluminescence of the CdSe spherical nanoc
rystals. (C) 1997 Elsevier Science Ltd.