Homoleptic Metal Carbonyl Cations of the Electron‐Rich Metals: Their Generation in Superacid Media Together with Their Spectroscopic and Structural Characterization

Abstract

have not been followed. The formulas of the neutral coordination compounds have not been enclosed by square brackets in order to distinguish more clearly the neutral compounds from ionic complexes and polyanions. the University of Hannover. During a sabbatical semester in 1989 with E Aubke in Vancouver, Canada, he became interested in superacids, and there laid the groundwork for this article with the discovery of the [Au(CO),/+ cation. Hisprincipal areas of activity are matrix-isolation spectroscopy of small, reactive molecules, especially in the fields of atmospheric and fluorine chemistry, as well as-in the past eight years-coordination chemistry in superacid media. where he has been a full professor since 1978. His research in physical inorganic chemistry has been concerned with the development of new superacid systems, their application in the generation of unusual, highly electrophilic nonmetallic, metallic, and organometallic cations, and their subsequent spectroscopic and structural studies. Felix Aubke is the recipient of ihe Killam Senior Faculty Research Fellowship (1987) and the Alexander von Humboldt Research Prize (1995). H~ has been very active in fluorine chemistry, and has hosted in Vancouver both the 10th (1982) and the 15th

Proton transfers are key elementary steps in ethylene polymerization on isolated chromium(III) silicates

“…2B). Finally, the calculated and observed blue-shifted values are consistent with the strongly cationic character of the Cr(III) centers, which induces electrostatic polarization of the CO molecular orbitals on coordination to a metal center (40,41).…”

The Carbonyl Chlorine(I) Cation [ClCO]+

“…Vibrational data calculated with these force constants are compared in Table 2 2 N m À1 [24] ). It follows that in the [ClCO] ion, CO is bonded in a very similar manner to that in the homoleptic metal carbonyl cations, [25] [M(CO) n ] m , where p bonding is strongly reduced and s bonding to M causes a polarization of the CO bond. [25] Hence the agreement in band positions between n 1 of [ClCO] ( Tables 1 and 2) and n 6 (F 1u ) of [Ir(CO) 6 ] 3 , [16] which motivated this work, is not surprising.…”

“…It follows that in the [ClCO] ion, CO is bonded in a very similar manner to that in the homoleptic metal carbonyl cations, [25] [M(CO) n ] m , where p bonding is strongly reduced and s bonding to M causes a polarization of the CO bond. [25] Hence the agreement in band positions between n 1 of [ClCO] ( Tables 1 and 2) and n 6 (F 1u ) of [Ir(CO) 6 ] 3 , [16] which motivated this work, is not surprising. The force constant F CCl of 6.51 Â 10 2 N m À1 is unusually large but characteristic for Cl ± C bonds involving sp-hybridized carbon as in C 2 Cl 2 (5.2 Â 10 2 N m À1 ; [26] calculated according to ref.…”

Homoleptic Isocyanide Metalates

“…Recent research, however, has provided us with the missing information about (M Mn, Tc, Re) that have been known for a longer time. [9] There are also blank areas in the field of isocyanide complex chemistry, which have remained for more than a century: homoleptic isocyanide…”