Origin of the Yellow Color
of Complex Nickel Oxides
George R. Rossman
Division of Geological and Planetary
California Institute of Technoogy
Pasadena, CA 91125
Robert D. Shannon, Robert K. Waring
Central Research and Development Department
E.E> du Pont de Nemours & Co.
Wilmington, Delaware 19898
Single-crystal optical absorption spectra of NiO, NiTiO3,
are presented or the purose of comparing the
spectra of yellow and green Ni2+ compounds.
Powder spectra of NiTiO3,
the ultraviolet region help elucidate the more intense charge tranfer
bands. Bright yellow color results when Ni2+ is
in a six-coordinated site significantly distorted from octahedral
symmetry. Increased absorption intensity occurs when the metal ion d-d bands are in
proximity to an ultraviolet charge transfer band.
last updated: 23-May-2019