The polymn. of acetylene was studied by thermal programmed reaction on nanoassembled model catalysts fabricated by soft landing of size-selected palladium Pdn (1≤n≤30) clusters on well-characterized MgO(100) thin films. In a single-pass heating cycle expt., benzene, butadiene, and butene were catalyzed with different selectivities as a function of cluster size: palladium atoms selectively produce benzene, and the highest selectivity for butadiene is obsd. for Pd6, whereas Pd20 reveals the highest selectivity for butene. These results provide an atom-by-atom observation of the selectivity of small palladium model catalysts, and extend toward small cluster sizes the study of Ormerod and Lambert on real palladium catalysts, where a structure sensitivity for the cyclotrimerization was obsd. (c) 2001 Academic Press. [on SciFinder(R)]     «

The polymn. of acetylene was studied by thermal programmed reaction on nanoassembled model catalysts fabricated by soft landing of size-selected palladium Pdn (1≤n≤30) clusters on well-characterized MgO(100) thin films. In a single-pass heating cycle expt., benzene, butadiene, and butene were catalyzed with different selectivities as a function of cluster size: palladium atoms selectively produce benzene, and the highest selectivity for butadiene is obsd. for Pd6, whereas Pd20 reveals the hi...     »

CAN 134:367233 35-3 Chemistry of Synthetic High Polymers Institut de Physique de la Matiere Condensee, Universite de Lausanne, Lausanne, Switz. Journal 0021-9517 7440-05-3 (Palladium) Role: CAT (Catalyst use), USES (Uses) (selectivity of acetylene polymn. atom by atom); 71-43-2 (Benzene); 106-99-0 (Butadiene); 25167-67-3 (Butene) Role: FMU (Formation, unclassified), FORM (Formation, nonpreparative) (selectivity of acetylene polymn. atom by atom); 74-86-2 (Acetylene) Role: RCT (Reactant), RACT (Reactant or reagent) (selectivity of acetylene polymn. atom by atom)     «

CAN 134:367233 35-3 Chemistry of Synthetic High Polymers Institut de Physique de la Matiere Condensee, Universite de Lausanne, Lausanne, Switz. Journal 0021-9517 7440-05-3 (Palladium) Role: CAT (Catalyst use), USES (Uses) (selectivity of acetylene polymn. atom by atom); 71-43-2 (Benzene); 106-99-0 (Butadiene); 25167-67-3 (Butene) Role: FMU (Formation, unclassified), FORM (Formation, nonpreparative) (selectivity of acetylene polymn. atom by atom); 74-86-2 (Acetylene) Role: RCT (Reactant), RAC...     »