Rotatory Dispersion of Metallic Co-ordination Compounds. I. Rotatory Dispersion in the First and the Second Absorption Bands of Cobaltic Compounds

Abstract

Abstract Rotatory dispersions in the visible and the ultraviolet region have been determined with cis-[Co en2Cl2]Cl and cis-[Co en2ClNO2]Cl, and dispersion curves have been analyzed by the method of successive approximation. Both the complexes show two inversive dispersions in the wave-length region of the “first absorption band”, and only one dispersion in the region of the “second absorption band”. The magnitude of those dispersions was found to be of the same order. An inversive dispersion was also observed in the region of the “specific absorption band”. In the wave-length region of the “first absorption band”, there appear two inversive dispersions due to the component absorptions, in accordance with the dichroism measurement. As for the inversive dispersions in the region of the “first absorption band”, the sign of the Cotton effect for the one is reverse to that for the other in the violeo-salt, but in the cis-chloronitro-salt, the Cotton effect is the same for the two components. A possibility of determining the absolute configuration was suggested from the rotatory dispersion curve in the wavelength region of the “first absorption band”.