Optical activity in racemic chromium(III) tartrate solution induced by circularly polarized irradiation

Journal article, 1977

Alkaline solutions of Cr(III) in racemic tartrate (=RS-T) become optically active when irradiated with circularly polarized light. This is assigned to the photo-inversions Λ-Cr (R-T)3X− → Δ-Cr(R-T)3X− and Δ-Cr(S-T)3X− → Λ-Cr(S-T)3X−, but ligand substitutions such as Cr(R-T)3 → Cr(R-T)2S-T, may occur as well. In the dark the activity slowly (k ca. 2 × 10−5 s−1) decays back to zero.