Zeeman infrared studies of Pr3+ centers in alkaline earth fluorides identif
y principal centers of tetragonal C-4v symmetry for CaF2 and SrF2. Crystal-
field analyses for these C-4v centers yield crystal-field parameters simila
r to those found for other trivalent rare-earth ions in CaF2 and SrF2. In B
aF2:Pr3+, the principal center has a Pr3+ site of trigonal C-3v symmetry. H
yperfine structure on sharp infrared-absorption lines of the tetragonal cen
ters are interpreted with magnetic-hyperfine constants calculated for the e
xcited multiplets together with parameters introduced to account for the ra
ndom-strain disorder.