Fig. 1. Top: vis-NIR spectra of 5a+ (red) and 5a2+ (blue) obtained by spectrophotometric titration of 5a (black) with BAHA (dichloromethane, 293 K). Bottom: vis-NIR spectrum of 9b2+ (red trace, SbCl6 salt, dichloromethane). Gray traces correspond to stepwise in situ reduction of 9b2+ with Zn powder. Apart from 9b+ and 9b, small amounts of 5b+ are also formed in contact with air.
