One and two photon spectra of Mn4+ in CS2TiF6 have been reported. A de
tailed analysis of these spectra testifies the presence of a strong el
ectron-vibration coupling in this system. A novel consequence of this
interaction, a reduction of the spin-orbit and trigonal field splittin
gs in the vibronic spectra as compared to the electronic origins, has
been observed for the first time.