Optical and Magnetic Properties and Geometry of Some d⁵ Ruthenium Complexes

Magnetic and optical properties of two d5 ruthenium-triphenylarsine complexes have been investigated. The complexes haveD4h., C2v, and D3h, molecular symmetries. The complex RuCl3[As(C6H5)3]2 has been found to possess C2V symmetry in the solid state and a trigonal-bipyramidal geometry (D3h) in solution. The D3h geometry has been established on the basis of the dipole moment measurement, optical spectra, and epr results. Optical spectra of all complexes have been correlated with the epr g values. One of the L → L charge-transfer transitions involving the π → π∗ transitions in the phenyl rings shows fine structures, better resolved than what has been reported for triphenylarsine ligand, and is considerably blue shifted in the trigonal-bipyramidal molecule, indicating a large amount of conjugation between arsenic and benzene through dπ-Pπ interactions. © 1973, American Chemical Society. All rights reserved.