Postprint version. Published in Solid State Communication, Volume 12, Issue 11, January 1, 1973, pages 1147-1148.
NOTE: At the time of publication, the author Richard B. Frankel was not yet affiliated with Cal Poly.
The definitive version is available at https://doi.org/10.1016/0038-1098(73)90131-2.
Far infrared absorption in cubic KMgF3 doped with Fe2+ is reported . A line is observed at 87cm−1, which is assigned to the (Γ5g → Γ3g, Γ4g) transition in the Fe2+. The reduction in the spin-orbit coupling from the free ion value has been predicted by Ham, Schwarz and O'Brien.