Metal chloride complexes, MCl4(THF)(2) (M = Zr, Hf) and (CP")MCl3 (M = Ti, Zr Hf, Cp" = eta(5)-C5H5, or eta(5)-C-5(CH3)(5)), were immobilized on a cyclopentadienyl surface of silica with a help of n-BuLi. Before this, the silica was modified with silane coupling agent, (EtO)(3)Si(CH2)(3)Cp, by applying saturating gas-solid reactions using atomic layer chemical vapor deposition (ALCVD) technique. The heterogeneous catalysts were characterized by FTIR, C-13 and Si-29 solid state NMR spectroscopies and elemental analyses. The prepared catalysts were tested in the polymerization of ethylene using methylaluminoxane (MAO) cocatalyst. Heterogeneous catalysts CpZrCl3/S and CpHfCl3/S (S = (EtO)(3)Si(CH2)(3)CP modified silica carrier) exhibited high activities and produced polyethylene with a narrow molar mass distribution. However, the corresponding titanium catalyst, CpTiCl3/S, exhibited low activity in ethylene polymerization and it dimerized and oligomerized ethylene. The activities of heterogeneous MCl4(THF)(2)/S (M = Zr, Hf) and [eta(5) -C-5(CH3)(5)]MCl3/S (M = Ti, Zr, Hf) catalysts were low and they all, except HfCl4(THF)(2)/S catalyst, produced polyethylene with a broad molar mass distribution. Catalyst leaching from the carrier was studied by treating the heterogeneous CpZrCl3/S catalyst with MAO. (C) 2002 Elsevier Science B.V. All rights reserved.