Optical Absorption Spectra of Crystal-Field Transitions in MnO

A technique is described for growing single crystals of MnO on MgO substrates by heating in a completely closed chamber of pressed powder MnO. The samples are thin enough that the five lowest-energy crystal-field absorption bands could easily be resolved in the optical absorption spectrum, whereas only three had been previously reported. From the transition energies the crystal-field parameters have been determined to be Dq = 1010 cm−1, B = 601 cm−1, and C = 3540 cm−1.