The optical properties of Cr3+ in KZnF3 have been investigated in the
4.2-625K temperature range by using steady-state and time-resolved las
er spectroscopy. The luminiscence shows a strong thermal quenching abo
ve 400K which can be analyzed on the basis of the quantum-mechanical s
ingle-configurational-coordinate model by using the Struck and Fonger
method. Emission lifetime measurements and time resolved spectra show
the existence of different Cr3+ centers in this host.