Synthesis and properties of novel inorganic red chromophore based on Cr4+ in tetrahedral coordination in Bi24Al2-Cr O39

The novel orange to red color Bi 24 Al 2- x Cr O 39 (0≤ ≤ 0.5) compounds were successfully synthesized by the solid state method. With increase of content, colors are tuned from dark red. X-ray diffraction patterns all samples indexed with cubic 2 structure space group I 23. oxidation in oxide is confirmed be +4 valence photoelectron spectroscopy (XPS) and electron paramagnetic resonance (EPR). Based on analysis UV–Visible spectrum, hue due d-d transition 4+ tetrahedral sites. as-synthesized also show excellent stability acid base environments.