Chemical and Bacteriological Studies of the Photochemical Reaction Product of Ammonium Hexachloroiridate(IV) 1

Abstract

Summary

When aqueous solutions of ammonium hexachloroiridate(IV) are irradiated with visible light in an ammonia atmosphere, a photochemical reaction occurs in which the complex (IrCl₆)^2- ion is converted through a less negatively charged intermediate to an apparently neutral species. Solutions so irradiated lose rather rapidly the absorption peaks at 416, 433, and 487 mμ and display a new peak at 325 mμ. Nonirradiated solutions are quite inhibitory to the growth of Escherichia coli, but irradiated solutions are much less so. Solutions irradiated for 5–7 hr markedly retard cytokinesis of the bacterial cells. It was tentatively proposed that the product responsible for this inhibition of cell division in the presence of continued cell elongation may be cis-tetrachlorodiammine-iridium.