Protonating metal-metal bonds: Changing the metal-metal interaction from bonding, to nonbonding, and to antibonding

Cr-Cr Quintuple Bonds: Ligand Topology and Interplay Between Metal-Metal and Metal-Ligand Bonding.

Chromium-chromium quintuple bonds seem to be approaching the lower limit for their bond distances, and this computational density functional theory study tries to explore the geometrical and electronic factors that determine that distance and to find ways to fine-tune it via the ligand choice. While for monodentate ligands the Cr-Cr distance is predicted to shorten as the Cr-Cr-L bond angle inc...

Metal-metal bonds in bimetallic surfaces.

Unwilling U-U bonding in U2@C80: cage-driven metal-metal bonds in di-uranium fullerenes.

Endohedral actinide fullerenes are rare and a little is known about their molecular properties. Here we characterize the U2@C80 system, which was recently detected experimentally by means of mass spectrometry (Akiyama et al., JACS, 2001, 123, 181). Theoretical calculations predict a stable endohedral system, (7)U2@C80, derived from the C80:7 IPR fullerene cage, with six unpaired electrons. Bond...

How Carbon Monoxide Bonds to Metal Surfaces

An analysis is presented of the similarities and differences in the bonding of CO to Ni(100), Ni(l1 l ) , Co(OOOl), Fe(1 lo), Cr(llO), and Ti(0001). The primary interactions in every case are the expected forward and back donation, the mixing of CO 5u with surface dzz and s states, and the mixing of CO 2a with metal dxryz. The latter interaction is dominant. Projections of the density of states...

Comparative study of ceramic-to-metal bonding.

Dentists and technicians have used dental ceramics associated with different types of alloys without taking into account the characteristics of compatibility of these materials. Knowing the properties of the alloy and ceramic used in metal/ceramic restorations is a key factor for treatment success. The purpose of this study was to evaluate the bond strength of a palladium-silver alloy (Pors-on ...