A series of distorted octahedral Cr(III) complexes containing tridentate S-, S/O- or N-donor ligands comprised of three distinct architectures: facultative {S(CH2CH2SC10H21)2 (L1) and O(CH2CH2SC10H21)2 (L2)}, tripodal {MeC(CH2SnC4H9)3 (L3), MeC(CH2SC10H21)3 (L4)} and macrocyclic {(C10H21)[9]aneN3 (L5), (C10H21)3[9]aneN3 (L6), with [9]aneN3 = 1,4,7-triazacyclononane} are reported and characterised spectroscopically. Activation of [CrCl3(L)] with MMAO produces very active ethylene trimerisation, oligomerisation and polymerisation catalysts, with significant dependence of the product distribution upon the ligand type present. The properties of the parent [CrCl3(L)] complexes are probed by cyclic voltammetry, UV-visible, EPR, EXAFS and XANES measurements, and the effects upon activation with Me3Al investigated similarly. Treatment with excess Me3Al leads to substitution of Cl ligands by Me groups, generation of an EPR silent Cr species (consistent with a change in the oxidation state of the Cr to either Cr(II) or Cr(IV)) and substantial dissociation of the neutral S and S/O-donor ligands.

H2S induces rapid sulfidation of the Rh nanoparticles at room temperature and completely poisons NO reduction by H2; SO2 elicits an equally rapid but subtle modification of nanoparticle structure but has little effect upon NO reduction at 523 K.

A series of distorted octahedral Cr(III) complexes containing tridentate S-, S/O- or N-donor ligands comprised of three distinct architectures: facultative {S(CH2CH2SC10H21)2 (L1) and O(CH2CH2SC10H21)2 (L2)}, tripodal {MeC(CH2SnC4H9)3 (L3), MeC(CH2SC10H21)3 (L4)} and macrocyclic {(C10H21)[9]aneN3 (L5), (C10H21)3[9]aneN3 (L6), with [9]aneN3 = 1,4,7-triazacyclononane} are reported and characterised spectroscopically. Activation of [CrCl3(L)] with MMAO produces very active ethylene trimerisation, oligomerisation and polymerisation catalysts, with significant dependence of the product distribution upon the ligand type present. The properties of the parent [CrCl3(L)] complexes are probed by cyclic voltammetry, UV-visible, EPR, EXAFS and XANES measurements, and the effects upon activation with Me3Al investigated similarly. Treatment with excess Me3Al leads to substitution of Cl ligands by Me groups, generation of an EPR silent Cr species (consistent with a change in the oxidation state of the Cr to either Cr(II) or Cr(IV)) and substantial dissociation of the neutral S and S/O-donor ligands.