1 Efficient Slurry-Phase Homopolymerization of Ethylene to Branched Polyethylenes Using α-Diimine Nickel(II) Catalysts Covalently Linked to Silica Supports Supporting Information Henri S. Schrekker,* Vasily Kotov, Peter Preishuber-Pflugl, Peter White, and Maurice Brookhart* Department of Chemistry, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3290, USA. Crystallographic information file for the X-Ray of -diimine nickel(II) complex 12a: Space Group and Cell Dimensions Monoclinic, P n a 13.7968(4) b 29.1659(8) c 15.4788(4) beta 114.999(1) Volume 5645.1(3)A**3 Empirical formula : C26 H36 Br2 N2 Ni O