Spectra of (A) 40 μM (H2O)2Cbi2+ in water, (B) 40 μM (H2O)2Cbi2+ immediately after spiking sufficient KCN to bring total cyanide concentration to 40 μM, (C) solution in B, after 1 h, (D) Solution in B, after 5 h. The inset shows the 580 nm absorbance due (CN)2Cbi. The decay of (CN)2Cbi to either diastereoisomer of CN(H2O)Cbi+ proceeds at two different rates. The fit to the sum of the two independent decay paths to the two diastereoisomers are depicted; the best fit half-lives are 7.2 and 61 min, respectively.