ISSN:
0538-8066
Schlagwort(e):
Chemistry
;
Physical Chemistry
Quelle:
Wiley InterScience Backfile Collection 1832-2000
Thema:
Chemie und Pharmazie
Notizen:
Reactions of Cu2 with several small molecules have been studied in the gas phase, under thermalized conditions at room temperature, in a fast-flow reactor. They fall into one of two categories. Cu2 does not react with O2, N2O, N2, H2, and CH4 at pressures up to 6 torr. This implies bimolecular rate constants of less than 5 × 10-15 cm3 s-1 at 6 torr He. Cu2 reacts with CO, NH3, C2H4, and C3H6 in a manner characteristic of association reactions. Second-order rate constants for all four of these reagents are dependent on total pressure. The reactions with CO, NH3, and C2H4 are in their low pressure limit at up to 6 torr He buffer gas pressure. The reaction with C3H6 begins to show fall-off behavior at pressures above 3 torr. Limiting low-pressure, third-order rate constants are 0.66 ± 0.10, 8.8 ± 1.2, 9.3 ± 1.4, and 85 ± 15 × 10-30 cm6 s-1 in He for CO, NH3, C2H4, and C3H6, respectively. Modeling studies of these rate constants imply that the association complexes are bound by at least 20 kcal mol-1 in the case of C2H4 and C3H6 and at least 25 kcal mol-1 in the other cases. The implications of these results for Cu-ligand bonding are developed in comparison with existing work on the interactions of these ligands with Cu atoms, larger clusters, and surfaces. © 1994 John Wiley & Sons, Inc.
Zusätzliches Material:
6 Ill.
Materialart:
Digitale Medien
URL:
http://dx.doi.org/10.1002/kin.550260110
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