Electronic absorption spectrum of nickel(II) in cubic perovskite fluorides. III. The ultraviolet spectrum

The ultraviolet absorption spectrum of divalent nickel is shown to be dependent on concentration for crystals of composition KMgxNil-xF3 with 0 < x < 1. The eight ultraviolet absorption bands have intensities which are directly related to the number of nearest neighbour nickel ions per nickel ion. Three of the bands can be assigned to states of the 1G and 1S terms while the remaining five have energies which can be equated to combinations of the energies of the excited singlet states lEga ITa2g and 1Aag and are simultaneous electronic excitations.