Reflectance spectra of non-stoichiometric titanium oxide, niobium oxide, and vanadium oxide

The diffuse reflectance spectra were obtained for nonstoichiometric titanium oxide, niobium oxide, and vanadium oxide in the spectral region from approximates 330 m mu to approximates 1300 m mu . The spectra are interpreted in terms of changes in the ultraviolet cut-off and changes in the visible reflectance. Data are given for the effect of composition on the effective band gap of these oxides. (auth)