The reactivity of heterobimetallic Zr/Co complexes linked by phosphinoamide ligands towards the oxidative addition of I(2) and alkyl halides is reported. These reactions are accompanied by dissociation of one phosphine ligand from Co and eta(2)-coordination to Zr. Addition of H(2) leads to both oxidative addition across the M-M bond and P-N bond cleavage.

We present an algorithm for computing Minkowski sums among surfaces of revolution and surfaces of linear extrusion, generated by slope-monotone closed curves. The special structure of these simple surfaces allows the process of normal matching between two surfaces to be expressed as an explicit equation. Based on this insight, we also present an efficient algorithm for computing the distance be...

We show that for polytopes P1, P2, . . . , Pr ⊂ R, each having ni ≥ d + 1 vertices, the Minkowski sum P1 + P2 + · · · + Pr cannot achieve the maximum of ∏ i ni vertices if r ≥ d. This complements a recent result of Fukuda & Weibel (2006), who show that this is possible for up to d − 1 summands. The result is obtained by combining methods from discrete geometry (Gale transforms) and topological ...