ION MOLECULE REACTION CHEMISTRY OF IONIC TRANSITION-METAL CARBONYL CLUSTER FRAGMENTS .1. LIGAND-EXCHANGE REACTIONS OF CR2(CO)Y(+) IONS
Additional Document Info
The ligand-exchange ion-molecule reaction chemistry of Cr2(CO)y+ ionic transition metal cluster fragments has been investigated by using a two-section ion cell Fourier transform ion cyclotron resonance mass spectrometer. Simple ligand-exchange reactions involving ligand (L) addition followed by metal-ligand (MCO) bond cleavage (i.e., an associative ligand-exchange mechanism) as well as ligand exchange involving metal-metal cleavage (i.e., addition of L to Cr2(CO)y+ followed by metal-metal bond cleavage) are observed. The branching ratios for reactions involving metal-metal bond cleavage increase as the metal-to-ligand ratio decreases. In addition, the ratio for simple ligand exchange to metal-metal bond cleavage is strongly dependent upon the nature of the reacting ligand (L). These data combined with collision-induced dissociation data for Cr2(CO)y+ ionic cluster fragments suggest that the Cr-Cr bond strength decreases as y is increased; i.e., the CrCr bond order is strongly dependent upon the ligand environment. 1990, American Chemical Society. All rights reserved.