Abstract
The widths and positions of the R1 fluorescence lines of trivalent chromium ions in nonequivalent lattice sites in lithium germanate crystals have been measured at temperatures from 24°K up to 200°K. The temperature dependences of the linewidths are explained in terms of microscopic strains, direct phonon processes, and two‐phonon Raman scattering processes. The temperature dependences of the lineshifts are attributed to two‐phonon virtual processes and direct phonon processes. The theraml changes in the widths and positions are found to be of the same order of magnitude. These results are compared with those from similar measurements on ruby‐ and chromium‐doped MgO.