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The isomorphous single crystals of M(ethylenediamine) 3 (NO 3 ) 2 , where M is Zn(II), Ni(II) and Co(II), exhibit macroscopic optical activity as predicted by their acentric space group. Axial circular dichroism measurements on these pure crystals show conclusively that spontaneous resolution has occurred. The axial circular dichroism and orthoaxial linear dichroism spectra of these pure crystals, and of Cu(II), Ni(II), Co(II), Mn(II) and Ru(II) doped into the Zn(en) 3 (NO 3 ) 2 crystal have been measured at ambient and cryogenic temperatures in the range from 7 to 35 kK. The first NO 3 − transition at 32.5 kK is assigned as 1 A ← 1 A based on its linear polarization and sign of rotational strength. The d-d transitions are assigned in the context of D 3 symmetry and reveal a small negative crystal field parameter k , consistent with theoretical prediction. A positive R for all d-d transitions is found to be associated with the Λ configuration for all of the complex ions, by correlation with the crystal and solution circular dichroism of Ru(en) 3 2+ .