The alexandrite-like Cr-doped aluminum oxalato complexes

The Cr-doped aluminum oxalato complexes were obtained by substituting Al with trace of Cr. Three types of products were obtained in two colors: blue (one) and red (two). One of the red crystallizes in the hexagonal crystal system with space group image. The two red complexes possess the color-change property under different light sources (fluorescence and incandescence lights) similar to alexandrite – the rare and expensive gemstone.