Ground-state splitting of antiferromagneticFeCO3

The ground-state splitting of antiferromagnetic ${\mathrm{FeCO}}_3$, caused by a trigonal crystal field with spin-orbit and exchange interactions is studied with an energy-level scheme different from that proposed in previous papers. The present results on the infrared and Raman transitions, especially on bands that were not assigned in past works, are in good agreement with the experimental data. The difference between the present and previous schemes is discussed.