A Pt- and Li-related line spectrum with a series of sharp lines between app
roximately 5000 and 8000 cm(-1) has been studied by excitation spectroscopy
combined with uniaxial stress. The intensity of the lines are favored when
the Pt and Li diffusion was carried out under Li-rich conditions. Phonon r
eplicas involving a h omega = 528.6 cm(-1) phonon are detected in the spect
rum. Thr phonon is suggested to be Li related and was also directly observe
d by local mode vibrational spectroscopy. Yet another set of replicas was o
bserved, displaced about Delta = 2229 cm(-1) to higher energies and was int
erpreted to originate from shake up effects in the final core state. Uniaxi
al stress spectroscopy reveals that shallow donor states are involved in th
e final state of the transitions.