Kent R. Mann

Electronic structures and spectra of hexakisphenylisocyanide complexes of Cr(0), Mo(0), W(0), Mn(I), and Mn(II)

Abstract Electronic absorption spectra of M(CNPh) 6 [M = Cr(0), Mo(0), W(0)], [Mn(CNPh) 6 ]Cl, and [Mn (CNPh) 6 ](PF 6 ) 2 are reported. Each of the M(CNPh) 6 complexes exhibits three intense metal-to-ligand charge transfer (MLCT) absorption bands between 20.8 and 32.7 kK. The lowest MLCT bands are observed at 29.9 and 31.1 kK in the electronic spectrum of Mn (CNPh) 6 + . Low energy bands at 18.2 and 20.4 kK in [Mn(CNPh) 6 ] 2+ are assigned to vibronic components of a σ(CNPh) → dπ charge transfer transition. The unique electronic structural properties of arylisocyanide complexes are apparently related to the π conjugation of aromatic ring orbitals with the out-of-plane π*(CN) function.

Mechanistic Aspects of Solar Energy Storage Reactions Involving Polynuclear Rhodium Isocyanide Complexes. Preparation of New Binuclear Isocyanide Complexes of Iridium, Cobalt, Nickel, and Ruthenium

We have found1 that 546 nm irradiation of solutions of the binuclear Rh(I) complex Rh2(bridge)4 2+ (bridge = 1, 3-diisocyano- propane), or Rh2 2+, in 12 M HCl(aq) results in clean conversion to H2 and a Rh(II) complex. The Rh(II) complex can also be prepared by Cl2 oxidation and has been structurally characterized.2 Recent work in our laboratory has shown that a thermal reaction generates the blue photoactive species, Rh4C12 4+, as follows: Open image in new window Notably, the photochemical step is uphill, as H2 reacts slowly with Rh2C12 2+ to regenerate Rh4C12 4+.